caitlyn had lived inside of me for all of these years. it was time to let her live. >> tonight, caitlyn jenner and diane sawyer. life as a transgender woman, two years after the bombshell. >> getting an olympic gold medal, the ultimate male. and glamorous woman of the year. come on. >> now, the backlash. >> we don't want you here. >> the politics. >> you don't give us equality and a fair shot, i'm coming after you. >> but is there a price to living a life fulfilled?

caitlyn jenner: the secrets of my life. a diane sawyer special. >> it was almost exactly two years ago this week, that a famous american had a stunning announcement. bruce jenner said that inside, there had always been a woman in brain and soul. it's had a lot of us hurtling into a maze of questions about what is gender and sexuality. we agreed to meet later. so, a note before we begin, when caitlyn jenner's book refers to bruce, it uses the pronoun he, and so will we. so, we'll head off to california to check in again. two years ago, this is where it began. bruce jenner, athlete, famous

dad on a reality show, waiting to stun the world by announcing inside he'd always been a woman. he greeted me at the door, 6'2" tall, welcoming and anxious. we'd never met before. >> how are you doing, baby? it's going to be an emotional roller coaster, but somehow i'm going to get through it. >> reporter: and when we sat down for the interview -- >> it's been really tough. but here i am, i'm still here. that's the good news. >> reporter: so bruce jenner is -- through tears, telling about the secrecy and confusion that had locked him into a kind of fortress his whole life. at a symbolic moment -- >> we're talking about all this stuff -- >> reporter: the ponytail came free. are you a woman? >> yes. for all intents and purposes. i am a woman. and that's very hard for bruce jenner to say, because why? i don't want to disappoint people. bruce lives a lie -- she is not a lie.

i can't do it anymore. >> reporter: in that moment, the anguished, uncertain man we knew as bruce said farewell. and two years later, as we pull up to a door at a house in malibu, someone very different comes out to say hello. >> welcome. >> reporter: remember me? >> i do. two years. >> reporter: casual, still welcoming, and this time, excited. >> we have so much to talk about! >> reporter: so what has it really been like, two years on the path living as a woman? is the rumor of doubt and regret true? we start with that question from two years ago, slightly rephrased. so let me start with the same question. caitlyn jenner is? >> happy. peaceful. peace in my soul. all of that confusion has left me. >> reporter: you told me two

years ago that a feminine side was a part of you. >> mm-hmm. duh. >> reporter: do you ever have doubt that you did the right thing? >> never. never had a doubt. i did the right thing. >> reporter: do you miss being bruce? >> no, not at all. not -- not even, not even close. not even close. >> reporter: she says in the old days bruce would look in a mirror and feel the anxiety of a body in a kind of duel with what was true inside. and when you look in the mirror now, you get up in the morning and look in the mirror? >> i'm excited about the day. for so many years i isolated myself. i wasn't -- i couldn't care less about the next day. now i do. >> reporter: what have you learned about being a woman that you didn't know before these last two years? >> i think i've learned a lot about compassion. >> caitlyn, have a great day. >> same to you! bye-bye.

>> reporter: she'd always said her dream was an ordinary day, an uneventful hello. >> i kind of come around the corner. and this guy goes walking by. and he just goes, "morning, ma'am." "morning," kept walking. and i just go, "how wonderful is that?" it's so simple. all right, we're going with the macaroni salad. big one. and i'll go with the potato salad. how are you today? >> reporter: you can see her two times a week at the supermarket, turning strangers into friends. >> this may be their only encounter with a trans person. i want it to be a good, joyful experience. >> hi, i'm so sorry to bother you. can i have a picture? my name is linnea. >> 1, 2, -- >> i probably take, you know, 20, 30, 40 selfies every day. >> i can't tell you what an inspiration you are to me. >> well, thank you. i appreciate that. what's your name?

>> matthew. >> matthew. get the camera out. let's do it. >> reporter: she says some people look at her because of her celebrity, but there are others who seem confounded or wary. >> i always wonder why they're staring. >> reporter: the transgender community has a word for it. when you feel someone is staring and singling you out, - it's called clocking. >> i had a guy actually ask for a selfie and said, "oh, bruce, could you give me a selfie?" and i looked at him. nobody's called me that in two years almost now. >> and? >> i said, "no problem." i want them to walk away saying, "oh, caitlyn jenner was so nice," you know? that trans people, yes, are approachable. and they're a vital part of our society. >> reporter: it's been her mission since that first magazine cover seen more than 3 billion times around the world. the cover that made your mouth drop. >> okay, the cover of "vanity fair."

>> reporter: what do you say about that picture? >> now, my feeling on that picture, i know, my kids that thought, "you know what? it's a little too much." but from my standpoint, i had suffered for 65 years, okay? to have a beautiful shot of my authentic self was important. and the shock value. >> reporter: you wanted the shock value? >> yes. i wanted to end the old bruce, my old life. and that picture did it. >> reporter: then she did it again four months later, in a room full of 6,000 people. including superstars like lebron james, derek jeter. it's the espys -- the academy awards of sport and she's getting the arthur ashe award for courage. and in this room there are a lot of people who remember bruce jenner, the 1976 king of the decathlon. a man of unmatched strength and speed, mastering the ten olympic events that are the highest test of human endurance, and raw masculine power. flying over the hurdles, heaving the shot put, so fast his

competitors go down in agony, but he takes a victory lap for the usa. and now that same person is walking down the aisle in a long white dress. >> i'd like to thank my family. >> reporter: there in the audience, the kardashian stepdaughters and his six jenner children. >> the biggest fear i've always had in coming out is i never wanted to hurt anyone else, most of all my family and my kids. i'm so, so grateful to have all of you in my life. thank you. >> reporter: also there, looking up at the person on stage, thousands of the toughest competitors of every sport. what were all of them thinking? >> these are my peers. these are, i'd been to the espys so many times. kind of a scary place to go. >> reporter: you said you wondered if they're looking at you trying to be supportive.

but thinking, "this" -- >> "what a freak." and i still wonder about that. some guys can accept it, some guys can't. >> reporter: did you look at their faces? or would it have been -- >> oh, i couldn't look at their faces. >> reporter: too daunting. she says she made it through this moment by thinking about the thousands and thousands of transgender people around the world, living in fear from bullying, homicide. in the largest national survey of transgender adults, 40% have attempted suicide. all those kids just trying to live in a world of discrimination and ridicule. >> if you want to call me names, make jokes, doubt my intentions, go ahead, because the reality is, i can take it. but for the thousands of kids out there coming to terms with being true to who they are, they shouldn't have to take it. >> reporter: a promise to be their champion.

and two years ago telling me she was setting out to create an inclusive world. >> what i'm doing is going to do some good. and we're going to change the world. >> reporter: back when bruce first emerged as caitlyn and the path ahead seemed sure. optimistic then? too optimistic? >> i was hoping then, okay? there was a lot of hope there. have i, in the last two years, had a bigger dose of reality? absolutely. >> reporter: coming up, the optimistic trailblazer gets burned. the hurricane of criticism from all sides. the distance from some of her family. and the physical and psychological journey of becoming caitlyn. whether you're after supreme performance...

...advanced intelligence... ...or breathtaking style... ...there's a c-class just for you. decisions, decisions, decisions. lease the c300 sedan for $389 a month at your local mercedes-benz dealer. mercedes-benz. the best or nothing. frappé or shake for $2. small mcdonald's smoothie, how do you top a deal like that? ♪ hurry in, only at mcdonald's. ♪ [bullfighting music] [burke] billy-goat ruffians. seen it. covered it. we know a thing or two because we've seen a thing or two. ♪ we are farmers. bum-pa-dum, bum-bum-bum-bum ♪ ...it shouldn't be whateverfleas and ticks. home... no, no no no no... seresto® kills and repels fleas and ticks for 8 continuous months - for effective protection in an easy-to-use, non-greasy collar. 8-month seresto®. from bayer.

only tylenol® rapid release gels have laser drilled holes. they release medicine fast, for fast pain relief. tylenol® (vo) more "dper rollres for mom" bounty is more absorbent, so the roll can last 50% longer than the leading ordinary brand. so you get more "life" per roll. bounty the quicker picker upper eggbut at outback,... we hunt for steak! for two weeks only, it's the great aussie steak hunt... come in, scratch off our 'aussie egg' and you could win free outback for an entire year! we're giving away thousands of other prizes... and everyone wins something, so hurry in!

at petsmart, we'll give a meal any to a pet in need. food so whralphie grabs grub, charlie chows down. and when peaeats, peanut eats. you buy a bag, we'll give a meal.

"20/20" continues with caitlyn jenner: the secrets of my life. >> i am transgender. >> reporter: in the two years since our interview so many young people said they felt safe enough to come forward. the estimate of transgender americans has now climbed from 700,000 to 1.4 million. >> what bruce was saying just really hit home for a lot of the struggles i felt. >> it makes me feel safe. they're being accepted. this shows me that i can be accepted. >> this is something i always i would just take to my grave,

because no one needed to know. and i didn't know there were others out there in the world that were like me. >> reporter: and like the little boy who lived in tarrytown, new york, 60 years ago. and had never even heard the word transgender. but at the age of 8 or 9, bruce jenner says he knew with certainty he was happier sneaking out in his sister or mother's clothes. >> i ate a lot of wheaties. >> reporter: a secret living inside the olympic icon on the wheaties box. and a secret still hidden when giving all those motivational speeches to corporate executives, dressed in a suit, but underneath often wearing a bra and pantyhose. >> i had my little suit on. i would walk off the stage, and i would feel like a liar. "you've just got no guts." gamble. gamble your best shot in life. dare to take risks. dare to take risks. life has got to be a great adventure or it's nothing. steal. steal every moment of happiness. live every day as if it's your last -- because we never know when that day is going to come. >> reporter: he fell into a severe depression. he started taking female hormones and felt better, but then lost his nerve and stopped.

deciding instead to put an instruction in his will for the day he died. >> yeah. >> reporter: that that was going to be part of your will, to be buried. >> yeah, it was. i thought that most of my life. i said, "if i -- if i go and when i'm buried," yeah, i wanted to be dressed as her, because that's the way i was going to heaven. i would say i'd kind of shock everybody when they come and visit the casket. >> reporter: through the decades, wishing he could be as brave as the other younger pioneers coming forward. >> i am a woman. i live my life as a woman. >> my mom has her first child who's a girl. we didn't know anything about this. >> i was assigned boy at birth. you know inside what you are.

>> reporter: she says it's harder to get your bearings at the age of 65 after a lifetime of secrets. at the time she decided to come out, she'd never even met another transgender person. in the beginning she was euphoric. >> caitlyn! caitlyn! >> reporter: but so uninformed, she was about to hit all the land mines. she was asked the hardest part of being a woman. >> figuring out what to wear. >> reporter: on "ellen," she seems hesitant when asked about marriage equality. >> that word marriage is really that that important to you, i can go with it. >> it's funny, you're a little not on board with it. >> no, i'm on board. >> reporter: she now says she is 100% on board. but there was also her reality show, which tackled some serious issues in the transgender world, but mixed in a lot of makeup, clothes, wine and the tone-deaf problems of privilege.

>> so many paparazzis. >> reporter: she complained about paparazzi, while her community faces homelessness and violence. not talking about paparazzi but talking about survival. >> survival. >> reporter: the question i think was -- and i'm going to go -- >> okay, hit me hard. >> reporter: the question was do you really feel what they're living? >> i feel it. and i see it. at the beginning of this whole thing, yes, i -- i knew absolutely nothing. yes, i made mistakes. on some subjects, i think i was insensitive, honestly, because i just didn't know any better. it's tough to take 65 years of being bruce and then, like, overnight everything changes. at first, you -- you don't know how to handle it. >> reporter: some people in the transgender community were so angry they shouted her down in

the streets. >> do you have any idea what's really happening out here? you are an insult. >> i am not representing you. i am representing myself. >> don't you [ bleep ] touch her! >> reporter: at the same time, internet trolls attacked her for being transgender. >> just brutal, brutal. it's like you don't even go there anymore. >> reporter: what's the kindest thing anyone's said? >> "i love you." people who have thought about suicide and said they wouldn't do it. >> reporter: did she save lives? >> absolutely. >> reporter: kids? >> absolutely she saved lives. >> reporter: this is professor jenny boylan at barnard college who has written the defining memoirs of being transgender. she's also a member of the board of glaad and appeared on the cait jenner reality show. she says we underestimate what it was for caitlyn to begin this new life so isolated. >> and how much did she know and

not know? >> she didn't know anything. i know some people roll their eyes at caitlyn. and i would ask them if they have ever had to do anything this hard as cait had to do, and i would ask them if they have gotten everything right the first time. >> reporter: and out in the country, almost overnight, a lot of americans were grappling with so many new ideas. gender fluidity, gender neutral pronouns. >> have you heard of gender neutral pronouns? >> yeah, like they, or them. >> i've heard of z, or zir? >> z? okay. >> reporter: we counted 58 gender options on facbeook. kids aren't surprised. >> genderqueer, and i know intersex. >> gender fluid, i've heard of that. >> reporter: but grown-ups? >> can you name any other gender identities? >> no. >> two for sure. >> that's way too many. >> reporter: professor boylan sensed for some americans this was building into a kind of

backlash. >> the fear is that the world is becoming an unstable place and that if there's -- if there's anything that we can depend on, it's that there are men and that there are women. >> reporter: and the trigger was the presidential election year. >> this is why trump might win. this is exactly why. >> it's the [ bleep ] lunacy that's going on in colleges these days. you're supposed to walk up to someone and say, "hi, nice to meet you, what pronoun should i use for your name?" >> reporter: the dating app tinder announced a new feature this week which gives users 37 different gender identity options. it's called, "why democrats lost the election." >> reporter: coming up, a backyard barbecue. controversy, parents taking sides. >> that's what i was told last year. that the kids need to get over it. >> i didn't say get over it.

>> reporter: in walks caitlyn jenner. what happens here? and what happens when a new president enters the fray? which makes your world infinitely bigger. a camera fast enough to catch this, and intelligent enough to understand what it sees. ♪ it connects you to home, and takes you anywhere you can imagine. which makes it infinitely amazing. so ammara, you're a verizon engineer, tell me, what's one really good reason why the samsung galaxy s8 is better on verizon? well we have the largest 4g lte network in america. yeah that's a pretty good reason. and the most reliable. uh-huh. and, with unlimited, you get full hd video. oh wow, yeah, that's, uh, two, maybe even three reasons right there. it's exactly three. okay. sure, whatever you say. (vo) if you really, really want the best, switch to verizon unlimited and get the galaxy s8 for just $15 a month.

i saw you take those phones, you know. no, you didn't. beggin' skinny strips or beggin' black label? there's two?! now this is a delicious dilemma! introducing new beggin' strips premium edition. twwwoooooo?!?! with real meat as ingredient one. everything to your liking? mmm mmmmm... new beggin' strips premium. becaussssseeee beggin'! how clean do you feel after(laughter)the bathroom? let's ask the experts. i feel as clean as a shimmering mermaid. that's because only cottonelle® has cleanripple® texture. designed to clean better... how cottonelle® do you feel? for my constipation, i switch laxatives.ed stimulant laxatives make your body go by forcefully stimulating the nerves in your colon. miralax is different. it works with the water in your body to hydrate and soften. unblocking your system naturally. miralax.

this scarf all that's my left to rememb... sayonara. what. she washed this like a month ago! the long lasting scent of gain. now available in matching scents across your entire laundry routine. a used car, truck, suv. that's smart. truecar can help. it's great for finding a new car, but you already knew that. it's also great for finding the perfect used car. you'll see what a fair price is, and you can connect with a truecar certified dealer. so, no matter what you're looking for... there it is. this is how buying a used car should be. this is truecar. ♪

>> reporter: caitlyn jenner has agreed to show up at a backyard barbecue. we've gathered together people on all sides of a national controversy. whether transgender students should get to choose their bathroom and locker rooms. some of these parents say yes. others say they have deep concerns about that and feel they don't often get to express their views. >> you want me to tell my story? >> reporter: yeah, do. this is holly, who tells the group about the day her son, a ninth grade student, came home

from school after someone was in the locker room. >> the first thing he said was, "mom, i've got bad news." and he said, "she's always been a girl. she's never been a boy. and now, all of a sudden, she comes back for the second semester, and says she's a boy, and she's using the boys' locker room. >> reporter: holly is a devout mormon. >> there are certain things that the religious community holds dear, and modesty and privacy, that's -- that's one of those things. they are never, ever, going to be okay with their daughter in an open locker room changing. in that locker room, they're never going to be okay with that. >> reporter: beth agrees it's about modesty. she is a christian who says that religious people often feel unfairly judged. >> that they are haters and bigots. >> reporter: theresa and her husband bo say it's not just the parents. theresa coaches girls' high school athletic teams. >> one of my juniors said, "coach, i don't know if i can handle it. i don't know if i can handle it." >> and there's always this fear of something new, something unknown. >> reporter: carliss says this sounds familiar. >> and my white college

basketball team, they didn't want to dress with me. i would go and dress somewhere else. >> reporter: but corrin thinks this is different. >> you can't go into a locker room one day and say, "you know, i'm going to be african-american today. and tomorrow i'm not." >> if history has taught us anything, it's that separate is not equal. that's scary to me. >> reporter: jenny and others here think that separating out transgender kids is just unkind. >> i have a son and a daughter. my daughter's seen my son naked a lot of times. she's not traumatized. shouldn't be a threatening thing. >> that's what i was told last year. that the kids need to get over it. that they need to get comfortable. >> i didn't say get over it. >> reporter: and then, the most famous transgender person in the world arrives. >> caitlyn, nice to see you. >> reporter: we had told the group she might come. >> you were one of my heroes growing up. you and i are both republicans, by the way, that's a great thing, and we're both men of faith -- -- women in the faith, excuse me. i mean, that's -- >> it's okay. pronouns. i don't get upset about all of

that. it's fine. i get it. let me ask you this question, 'cause you are a person of faith. from your standpoint, as far as faith, how do you see this issue? >> i think that pope francis said it best, god loves us all. >> reporter: and then she surprises the group about which people have attacked her the most harshly. >> out of all of the negative mail i got, especially at the beginning, was from people of faith. >> that is horrible, especially coming from people who profess to believe in god. >> reporter: holly says that has to change. and notes when she went public asking for separate stalls for kids in locker rooms -- >> i also was a recipient of unspeakable hate mail and death threats. it was just absolutely horrible. i think that we need to come to a point where we say, "we're not

going to agree on everything, but for heaven's sakes, quit bullying." >> reporter: and then there is someone who weighs in saying it's possible to find common ground across this national divide. he's dr. david vannasdall, superintendent of the arcadia public schools in california. and says the real issue is privacy for all kids and that means practical solutions. >> the second we were able to get all the attorneys out of the room and remind ourselves what we do best. >> reporter: his schools have nearly 10,000 students. a few years ago, after parents and teachers decided to talk together, the school now has some gender neutral bathrooms which he says are freely used by all kids. and across the country, in the locker rooms, some schools use inexpensive curtains for those who are transgender and those who are not. >> we're going on six years, multiple students that are managing themselves with our behind-the-scenes support without impacting any students. it's been very successful. >> reporter: and do you have any parents objecting?

>> no. no, we don't. >> reporter: and vanasdall says the students have responded with friendship for their transgender classmates. >> which should tell us adults something that they care more about what's in the heart than the anatomy. >> reporter: from this backyard, a lesson in respect for a contentious and polarized nation. the person sitting in the front has taken hits from all sides. on her tv show, her transgender friends are horrified by her republican politics. >> republicans, your people, they don't like us. >> here's the deal. yes, i did vote for trump. >> reporter: she says she believed donald trump was personally inclusive and that he would surprise everyone on lgbt issues. here at the convention. >> i will protect our lgbtq citizens. >> reporter: and when president trump saw her at his inauguration -- >> he wanted me to come play golf with him. >> reporter: but, just 34 days into his administration, she was

shocked. he revoked an obama directive designed to strengthen federal protection of transgender kid on their bathroom choice. >> this administration for me, it was extremely, extremely disappointing. here's the dealbreaker with the republican party. and the dealbreaker is, you mess with my community, you don't give us equality and a fair shot, i'm coming after you. >> reporter: back at our barbecue, it's time for caitlyn to say good-bye. >> thank you. >> reporter: but when i tell the group, i'm heading off to interview parents of transgender kids, some of them decide to come with me to the nearby coffee shop. >> nice to meet you. >> reporter: dr. vannasdall is greeted by a woman who says her transgender son was in one of his schools and thanks him for his open heart. we start by hearing family stories. jody told about her little girl who knew something was not right at the age of 3.

people think at 3, it's just not possible. >> my kid, at 3, said, "everyone thinks i'm a girl, and i'm not." and then i said, "however you feel is fine." and then penelope said, "no, i don't feel like a boy, mama. i am a boy." that's as clear as it gets. >> reporter: parents danielle and stephen say like a lot of people, they were rocked when their 9-year-old boy started asking about a sex change. >> and i remember walking out and going into our bedroom and going, "oh, my god. like, oh, my goodness." >> reporter: marsha confides she used to believe that being transgender was a choice. until her daughter said she was a boy and fell into a terrible depression at not being understood. marsha says think of these kids just trying to use a bathroom. >> somebody called security on him. and so they took him out. and they put those twist ties on, you know, those zip ties on him until he could prove that

was the restroom that he was supposed to go into. >> i'm sorry that you're uncomfortable. i don't want you to be uncomfortable. but i don't want my baby to kill herself. >> reporter: and gina says for every parent, nothing is more compelling than your anguished child. >> suicidal. extremely depressed. was hurting himself. >> reporter: finally finding happiness. >> when he learned about being transgender, it was like this light went off in him. that's what he was. >> reporter: she's happy now? >> for the first year in about three or four years, she wanted to have a big birthday party. >> he is a karate champion. you know, he goes to karate tournaments twice a year and wins. he loves math. he's probably the giddiest kid in the family, talks the most. >> reporter: one parent from the barbecue asks how she can help. >> what can our children do to be more supportive of your children in the school scene? >> i think, i mean, that's the greatest place to start is meet them.

meet the people who aren't like you. and get to know them as people, as human beings. >> i so appreciate all the people who are here that want to hear these stories. because, as a mother, this is the kind of hope that i get, that's what bridges this gap. >> you have a choice to operate from fear, and that sends you one direction. or to operate from possibility, hope, and opportunity, and that sends you on another path. >> reporter: next, the latest science in transgender. what makes a man a man, and a woman a woman? and caitlyn's most personal decision. he- [gas pouring]

[slurps loudly] [engine starting] [loud slurping continues] [h♪avy sigh] real meal for five bucks. real meal for five bucks. real meal for five bucks. real meal for five bucks. real meal for five bucks. [deep breath] finger lickin', finger lickin', finger lickin'... gooooood!!!

yoit's shocking actually.ey put in tyson fun nuggets. they're made with real 100% all-natural ingredients. like white meat chicken... and that's it. keep it real. keep it tyson.

"20/20" continues with caitlyn jenner: the secrets of my life. >> reporter: almost every day someone goes roaring through the hills of malibu. there, a woman in a dune buggy. and there she is again flying her plane over the houses of her children along the beach. a person who spent her childhood loving cars, playing sports and

knowing even then she was female. >> every trans person asks that question, why? why me? why is this in my head? there's got to be something biological to this. >> for a lot of scientists, one intriguing clue on that question comes from identical twins. >> we are the twins. >> reporter: these are 26-years-old southern girls. >> we can finish each other's sentences, each other's thoughts, each other's feelings. >> reporter: identical girls, whose parents were once sure they were identical boys. we've chosen not to show their full faces. like so many other trans people, they're concerned about their safety. but they say, they knew they were being forced into the wrong gender when they were 3 years old. >> and the best way i can explain it, is you're trying to claw your way out of this coffin that just keeps getting dirt put over it. >> it's a prison. essentially it's a prison. >> reporter: and here's an

interesting finding. if you have one identical twin who is transgender, there is a 39% probability the other will be, too. signaling something is genetic. and consider what happened to these two identical twin boys, who were separated at birth, raised in entirely different homes. and yet still somehow, by the age of 8, they both knew they were in fact girls. born this way? >> born this way, absolutely. >> reporter: this is dr. jeremi carswell, dr. norman spack of the gender clinic at prestigious boston children's hospital. they remind parents it's common for little kids to experiment with gender as they're growing up. it doesn't mean anything. but they say a transgender child is different, not just experimenting. especially as they head toward puberty. they will be insistently certain their anatomy is wrong. >> i had a 7-year-old who looked at me and said, "god made a mistake and this needs to come off."

>> reporter: so you're saying that you're not going to talk a child into being transgender. >> no. >> no. >> reporter: that can't happen unwittingly, accidentally. it just doesn't happen? >> everybody i know who has tried to change somebody's gender identity -- they can't do it. >> reporter: why is that? over the last two years, we've stayed in touch with dozens of experts. many of whom are increasingly intrigued by the possibility of a biological event in the womb. the brain begins to form early in the first weeks of life. it's two weeks later the genitals begin to take shape. is it possible that at some point, signals get mixed, the brain gets one gender instruction, the anatomy gets another? one thing is clear, if there's a conflict, it's the brain that will win. but dr. spack wants everyone to know the american psychiatric association says it is not a mental disorder to be transgender. but what is the proof of that?

>> i think the proof was that it didn't require psychotropic medication to make it better. but that as soon as the patients were treated in the hormones of the gender that they affirm, they were instantly better. >> reporter: as if the brain craves a hormone the body can't produce. caitlyn jenner says female hormones almost instantly quieted the inner conflict that caused depression. >> it's a tough road. it's a tough, tough road. >> reporter: and she says since coming out, she's been lucky to have the money to change her appearance -- jawline, her forehead, her breasts. and she has just announced in the book she has become one of the 12% of trans women who go on to get what's called final surgery. >> it's about what's between your ears and who you are as a person. it's your soul, okay? >> reporter: she writes, after much deliberation, i had the final surgery in 2017. the surgery was a success, and i feel not only wonderful but liberated. so all of you can stop staring.

>> but i wasn't less of a woman the day before i had the surgery than i was the day after i had the surgery. because that did not define who i am as a human being. >> reporter: no regrets? >> none whatsoever. >> reporter: then she issues a kind of social warning, saying this is a topic only a transgender person can bring up, and the rest of us should never ask. so how did you decide to put it in the book at all? >> this book is about honesty. but that doesn't mean in the future that i have to talk about it, that i'm going to dwell. the media may. but i am not going to dwell on that subject. you know, and i would make a suggestion to all people out there, don't ask the question. it's not an appropriate question to ask any trans person. >> reporter: coming up, looking back at her life and what she says may be the most

unforgivable thing she's done. this is a quote from the book. "if god refuses to make peace with me, this will be the primary reason." re headed. because as we live longer... and markets continue to rise and fall... predictable is one thing you need in retirement to help protect what you've earned and ensure it lasts. introducing brighthouse financial. a new company established by metlife to specialize in annuities & life insurance. talk to your advisor about a brighter financial future. ♪ it's not carbonation. those bubbles are celebrating. ♪ right now, get $1 any size soft drink. only at mcdonald's. ♪ find fast relief behind the counter allergies with nasal congestion? with claritin-d. [ upbeat music ] strut past that aisle for the allergy relief

that starts working in as little as 30 minutes and contains the best oral decongestant. live claritin clear, with claritin-d. ...studying to be a dentist and she gave me advice. she said dad... ... go pro with crest pro-health. 4 out of 5 dentists confirm these crest pro-health products... &help maintain a professional clean. crest pro-health... ...really brought my mouth... ...to the next level. go pro with crest pro-health what's the best way to get v8 or a fancy juice store?s? ready, go! hi, juice universe? one large rutabaga, with eggplant... done! that's not fair. glad i had a v8. the original way to fuel your day.

"20/20" continues with caitlyn jenner: the secrets of my life. >> cute little kid, looks just like me, doesn't me? say 1, 2, --

>> reporter: home movies of a high-spirited, high-energy dream dad. >> wave good-bye to mommy. good-bye. >> reporter: the athlete effortlessly lifting his children in the air. >> come on, get on your bike, let's go for it. >> reporter: this picture is still her favorite. jenner children, the kardashian stepchildren all together. >> i'm so glad it's in my memory bank. >> reporter: but there is always a story the pictures don't tell. like how a dream dad was wrestling with gender, falling into a depression, retreating into isolated house on a hill for nearly a decade. >> i lived about two hills over here. and i just kind of dropped out of society. and also, i dropped out as a parent. >> reporter: a decade in which the jenner children rarely saw him. and later, after he emerged, he was soon absorbed in the kardashian show. but at the time of the announcement two years ago, jenner's four older children sent word they wanted to be supportive. to go on camera, to say the past

is past and they're happy to see their dad's suffering gone. >> and i just held his hand and i cried with him, and i just told him how proud of him i was and how inspired i was. >> the first thing i thought was just like, "it finally makes sense." >> yeah. >> reporter: they still calling you dad? >> yeah. still calls me dad. >> reporter: two years ago when life held out the possibility that caitlyn jenner could now be present every day, in a way that bruce was not. >> some i have remained very close to. and a couple of them, i'm a little more distant. i have to admit i'll sit here and wonder, is it because of me transitioning? or is it because their life is so busy that they don't call, like, all the time? but every parent goes through that. i've got all these kids, all hard-working. all doing very well. >> who calls the most? >> none of them. nobody calls that much. i mostly reach out to them. obviously the jenner side calls more.

but they all have their own lives. >> reporter: so what about her life ahead? someone new at her side? as we looked through old pictures, we saw some of the girls bruce had loved. >> i had this crush. and why i remember her name, this girl right here, joyce nelson. yeah, i had a crush on her when i was in kindergarten. yes! >> reporter: there were also the three marriages. the last one playing out in reality tv. with bruce often a kind of punching bag. >> do i talk to, obviously the last one, kris, all the time? no. she's kind of moved on. i certainly have moved on. but we're fine with each other. >> reporter: at this point someone joins us. older sister pam. >> i would love to see her have a companion someday. no idea what gender that companion would be, actually. i'm not sure you -- >> a nice person. >> a nice person. >> i don't -- i don't see really even dating in my future.

i have not been approached. i've never been out on a date with -- >> reporter: in two years? >> yeah. yeah. never been out. i just have a lot of friends. >> reporter: that doesn't necessarily heal loneliness. >> my life revolves around my kids. and they'll be in my life until the day i die. >> reporter: by the way, this song was written by her son, brandon jenner, and his wife leah. ♪ every time you fall i fall ♪ every time you cry i cry >> reporter: and caitlyn jenner says she has a lesson for every parent, and an irony.

she writes, if god refuses to make peace with me, that will be the reason. >> there's no excuse for not being a good parent, no matter how many problems that you have. no excuse for that. >> reporter: and tonight, the jenner children have sent word they preferred to stay private. instead giving us a statement, "we love our father and have deep admiration for her bravery. every has unique milestones, but we can honestly say caitlyn's gender transition has brought our family closer." coming up, a final word about what might have been. and a

we invited top stylists to try our hair care products. i'm dying to know what this is! so soft, feels amazing. then we revealed they've been using suave professionals. suave?! they couldn't believe it, but they're believers now. i had no idea! it's incredible. fantastic shine. so beautiful! this definitely changes my mind about suave. trying is believing. suave professionals. trust the proof, not the price tag. ♪ ♪i'ma wade, i'ma wave through the waters♪ ♪tell the tide, "don't move" ♪freedom! freedom! i can't move ♪freedom, cut me loose! ♪freedom! freedom! where are you?♪ ♪cause i need freedom too! ♪freedom! freedom! freedom! freedom!♪ ♪what you want from me? ♪is it truth you seek? oh father can you hear meee...ooow?♪

at petsmart, we'll give a meal any to a pet in need. food so whralphie grabs grub, charlie chows down. and when peaeats, peanut eats. you buy a bag, we'll give a meal. essential for him, but maybe not for people with rheumatoid arthritis. because there are options. like an "unjection™". xeljanz xr. a once daily pill for adults with moderate to severe ra for whom methotrexate did not work well. xeljanz xr can reduce pain, swelling and joint damage, even without methotrexate. xeljanz xr can lower your ability to fight infections, including tuberculosis. serious, sometimes fatal infections, lymphoma and other cancers have happened. don't start xeljanz xr if you have an infection. tears in the stomach or intestines, low blood cell counts and higher liver tests and cholesterol levels have happened. your doctor should perform blood tests before you start and while taking xeljanz xr, and monitor certain liver tests. tell your doctor if you were in a region where fungal infections are common

and if you have had tb, hepatitis b or c, or are prone to infections. needles. fine for some. but for you, one pill a day may provide symptom relief. ask your doctor about xeljanz xr. an "unjection™". eggbut at outback,... we hunt for steak! for two weeks only, it's the great aussie steak hunt... come in, scratch off our 'aussie egg' and you could win free outback for an entire year! we're giving away thousands of other prizes... and everyone wins something, so hurry in! ♪

yeah, the room's kind of a mess. >> reporter: a sprawling closet filled with clothes. >> this is the one i wore to the oscar night. >> reporter: some of them sent by the kardashians. >> kim gave me that one. >> reporter: others are just sentimental from the days when caitlyn could only be herself in secret. >> i have a terrible tendency to hold onto things and it's like, "i can't get rid of it," because it represents something in my past. >> reporter: look at the sunglasses alone. >> these are actually, like, very old. i think actually i stole these from kris a long time ago. >> reporter: as we walk into the hall, there's a table with a lifetime of awards. and she says she wants to concentrate now on raising money for transgender issues, her foundation and asking corporations to help more with crushing discrimination. >> the unemployment rate. yeah, it just, you know, it's staggering. especially for trans women of color.

>> reporter: do you think in your lifetime, my lifetime, that we'll see full acceptance? >> no. i don't think we'll ever see full acceptance. is it going to get better? i hope so. and i hope that i'm part of that. i want to fight this fight. i'm playing in the fourth quarter of life. you know? and i don't have that many years left. >> reporter: a sense of urgency. it's in the book. she writes, don't wait until it's too late to be the person you really are with the people you really love. the dedication is to her brother who died right after the olympics and her father, her hero, a decorated soldier who landed on omaha beach. >> and the reason i dedicated it to them, 'cause they're the only two in my family who's never heard this story. >> reporter: you're not worried. it would've broken his heart for his son -- >> my dad was a good person. a kind soul. i think the initial shock would've been really difficult

on him. like, "huh?" he'd go, "what? you, what are you?" but, you know -- and i'm sure he's looking down on me, watching all of this. you know, he's actually buried in arlington, washington, d.c., national cemetery. so, yeah, he's there with all his army buddies looking down and saying, "go, caitlyn." >> and in the end, maybe it's all about widening our circle of understanding together. experts say the most powerful way to do that is to listen to others tell their story. the book is on sale on tuesday. i'm diane sawyer. for all of us at "20/20," good night.

>> a chester county teacher's aid is charged with a despicable crime and a major city plunges into darkness. that's next. ♪ ♪ "action news," delaware valley's leading news program with ji jim gardner. ♪ >> this is arthur age 67. he was a teacher aide at