Transcript for 'It was like a dream': Trans advocate Jazz Jennings on gender confirmation surgery
Jazz Jennings has been had a vocal advocate for transgender kids ever since she first spoke to Barbara Walters more than ten years ago. And each step of the way she's allowed us to document her process, from socializing to pausing puberty, and now the ultimate step of gender confirmation surgery. It was like a dream. This is a moment that I had always envisioned. It's a dream she's had for as long as she can remember. What happens in the good fairy dream? So when I was 2 years old, I went up to Moy mom and asked her when is the good fairy going to come with her magic wand and turn my penis into a valujet in a? Were you 2? Yeah. And this fairy dream is about to become reality. Something I've always wanted. Right up here, jazz. Jazz is arguably the most famous transgender teen in the country carrying the torch on behalf of the transkids rights for the last decade. Her work recognized from glaad to the human rights cane. The hatred, rejection and cruelty and bullying must stop. Known for her advocates toe gender neutral bath rooms, she's tackled some of the most divisive issues head on. You've been so public about your entire path. Does that make it easier or harder to be a trans teen, do you think? It just depends I guess. I think for me, I've always within so honest about who I am as a person and being a transgender something I couldn't hide no matter what. There's my stretcher. She's about to undergo her gender transformation surgery. Final step. Transitioning. A procedure in her case essentially refashions male genitalia into the female equivalent. This is the last thing that will validate my identity as a woman. There's nothing else. I get to be in my body as I've wanted and I can live my life as just jazz. What do you look forward to the most, the moment you wake up from the surgery? I think just looking at my vagina for the first time. It's going to be like a new birth, you know. What do you say to your critics who would argue it's tmi? I don't need this much information about bottom surgery. Yeah, it is personal and uncomfortable for some individuals, but how are we going to learn if someone doesn't step up to the plate and share their story? It's been a long and winding road, one we've documented for more than a decade. Hi. Hi. Can I come in your house? Yes. The Jennings first opened up to Barbara Walters back in 2007. Your child was born a boy and now you call him a girl? Yes? Yes. At the time jazz was just 6 years old. One of the youngest documented cases of a child transitsing from male to female. If people say to you are you a boy or a girl, what do you say? A girl. Mom! The Jennings, who have three older kid, faced backlash from allowing jazz as such a young age to present pubically as trans. More than ten years later, it's something they still find themselves defending. You've had to put up with a lot of withering criticism. What after all these years do you say to people who still have those doubts? I would rather have a living daughter than a dead son, and I know that if I didn't let this child be who she wanted to be there's a good chance she wouldn't be with us today. There are some people who will forever think maybe her parents brainwashed her, maybe she was too young to know, maybe, maybe, maybe. I really, really hate it. This was all me. This is how I felt. They just embraced and loved me for who I was. Over the years, we've checked in with jazz, that precocious little girl who grew into a confident pre-teen, navigating the awkward middle school years. I don't care what he thinks about me if that's bad. If it's good then I love him. With adolescence looming, jazz along with her parents decided to use blockers to medically pause male puberty. They block any facial hair I might get or armpit hair, maybe like just so I don't look like a boy or even getting a deep voice also. Then on the verge of high school, the female hormone. So this is like -- this is estrogen pill that I take. I started getting breasts, softer features, everything more feminine, and it's what I've always wanted. She calls it a life-saving pill. I have no regrets because it allowed me to prevent myself from going through male puberty. I feel like that's why my disphoria hasn't been so bad and I see the growth that I am on the inside but not every transgender has the opportunity to do that. Push yourself. Show's also been open about her struggles, her binge eating, coping with anxiety, depression. I knew that my weight was a problem, but I didn't realize that it could affect something that I've been waiting for my entire life. All documented in her award-winning tlc reality show "I am jazz." So happy and excited. In the upcoming fifth season cameras capturing the final steps of her transition. One that involved overcoming obstacles. It's been hard, you know. I've had to do a lot of things to prepare for this surgery. I had to lose 30 pounds, and that was real, really challenging, because I had Han addiction to food, and it was something that Goff me comfort, and I had to let that go because the surgery is so much more important to me than any slice of cake or pizza. But that surgery would be complicated because of those hormone blockers, the same ones jazz says helped save her life. Being on the blockers is something that I don't regret at all. The only, you know, downside to it was that I didn't have enough growth down below so there wasn't enough tissue to work with when it came to the surgery and it was very challenging to find a doctor, a surgeon, who was willing to perform the operation on me just because I'm such a difficult case. Jazz and her family south a brand-new ground breaking technique. They are using the peritoneum and as long as it's successful I'm happy. And if successful, she hopes it will pave the way for the next trans girls. Is there one thing you're most looking forward to after the surgery? Wearing leggings. Love. You with the team of three surgeons, the surgery lasting almost five hours. We have news. We have news. Yes. It's a girl. It's a girl. Her warrants right there -- her parents right there throughout. I love you so much. I woke up the morning of the surgery, and I don't think I've ever been that happy in my entirely. Like pure positive energy. How are you feeling? It's been nine weeks since jazz's surgery, and we head to Florida to visit her at home. Just a little something. So nice of you to do that. Really. Leggings. Leggings. Oh, my gosh. While she's now on her way to a full recovery, getting there has not been easy. There was a complication. Hi to go back in for another procedure but it was all part of the journey. The good thing though is that it was only cosmetic and external, so it wasn't too dramatic. Your life was never in danger? No. My life wasn't in danger. Through the ups and downs, jazz's parents have been a constant source of support. This is the big award that we got for the show. She was the grand marshalls at the New York City pride parade. These hold a point of pride in your home. Yes, yes, one of the proudest days ever when the president tells your 14-year-old that they are proud of her. One thing we learned early on about jazz she was articulate and we just determined it was really difficult to not share her with the world. In many ways, she's still that girl we first met a decade ago, but now at 18, the trans child advocate to trans adult, tackling the harsh realities, discrimination in the workplace, unemployment, homelessness and even higher rates of murder. Do you see yourself continuing to, you know, carry the banner for trans rights? More and more I'm thinking about tpg my advocates. -- My advocacy. I want equality for everyone, and if we can embrace the variety of who we are, and all of our differences and come together with new ideas and ways of thinking, then I think this world can be a better place. ??? In my own corner and my own little chair ??? For a girl who sang about Cinderella. ??? I can be whatever I want to be ?????? on the wings of my fancy ??? Yaz is one step closer to that fairy tale ending. ??? The world will open its arms to me ??? The newest season of "I am jazz" premiers January 1st on tlc.
This transcript has been automatically generated and may not be 100% accurate.