When Sabine Bartlett was 13 her mother, who had been divorced from her father for a decade, transitioned from female to male.
Even though Sabine had grown up in a Unitarian Church with lots of gender and sexual diversity, Sabine knew little about being transgender.
Now 16 and living in Somerville, Mass., Sabine remembers her mother was "never particularly feminine," but began to "present as more butch."
"I came home from a trip with to my Dad's house and mom sat me down on the couch and told me she was going to transition," she said. "It's hard to face the fact that someone who is close to you changes at all -- especially a change that big."
An estimated 750,000 Americans identify as transgender -- about .3 percent of the population, according to the Williams Institute, an LGBT think tank at the UCLA Law School.
A National Transgender Discrimination Survey of nearly 6,000 respondents revealed that about 38 percent were parents and at least 18 percent had at least one dependent child.
The 2011 survey was conducted by the National Center for Transgender Equality.
Transgender parents say that finding their true identity can be lifesaving for them, but at the same time, devastating for their children -- at least for a period of time.
"At first I felt a sense of loss, until a year later, when I saw that my mom was a much happier person," said Sabine. "Now, I am cool with this."
Just last week, New York City's Mel Wymore, a transgender man who is running for city council, discussed the difficulty his two children had during his transition from female to male in 2009.
"We have had very deep conversations and some negotiations around what makes them comfortable," he told the New York Times, adding the children are still allowed to call him, "Mom."
But Dana Beyer, a former surgeon who has run twice for Maryland state delegate, said, "Time heals all wounds if you allow it to."
Beyer hopes to be the nation's first elected transgender politician at the state level.
"I am trying as an advocate to normalize this as another medical condition," said Beyer, 60, who was born intersex [with a small penis and a partial uterus] and raised a boy. "No one knew what that meant then."
She had known since the age of 7 she was a girl, and like others who felt trapped in the wrong body, Beyer said she suffered from depression and even post-traumatic stress.
Beyer transitioned a decade ago when her sons were 14 and 17.
"The younger boy living at home at time no problem and this washed off his back," she said. "My older son was away at school and didn't observe the process and was little more uptight."
At graduation, her older son couldn't introduce his father, now a woman, to his friends.
The brothers wondered if his father's transgenderism meant they were gay. "It's an existential issue," said Beyer. "My father becomes my mother -- what does that mean for me?"
So she matter-of-factly asked them, "OK, guys, do you like boys or girls? … It turns out they were straight guys."
Now both boys are accepting of her new identity, calling her, "Dana."
"Secrecy is the most damaging thing," said Beyer. "You need to let them know you love them and it has nothing to do with them, but you can't hide it. Kids know if you are lying."
Other parents say that taking on a new identity came at a huge cost.
Sarah, not her real name, lost her job, a respectable life in the suburbs and her children when she transitioned from male to female.
"I lost pretty much everything," said the 50-year-old Boston waitress. "I had the American dream. A house with an in-ground pool, I was politically active and president of the Chamber of Commerce."
But the hardest was the loss of her children -- a 27-year-old daughter from a first marriage and a 17-year-old daughter and 16-year-old son from a second marriage.
"I never really understood my sexuality growing up," she said. "I didn't know what gay and transgender were. I thought, 'Oh my god, this is sick.' It was a major taboo in my generation."
Still, Sarah knew something was wrong. "I imagined being female, I was jealous of girls in dresses and I always kept it to myself. I lived in a male world and thought this is what I have to be."
As a man, his world revolved around his children. "I was very close to them. My marriage was on the rocks, but I wanted children -- I loved them so much."
Sarah eventually became depressed and attempted suicide. When the marriage fell apart, Sarah's wife served her with an order of protection and the court revoked her rights as a parent.
Sarah said the children were "scared and devastated" and aligned themselves with their mother.
Now, after facial feminization surgery in 2007 and sex reassignment surgery in 2009, Sarah said she has found inner happiness, but her heart still aches for her children.
"I will always be there for them when they want me," she said. "I just sit here and wait. It's all I can do. Everyone believes it was a very selfish act, maybe so in some way, but it was life or death for me."
For other transgender parents, one child was accepting and another sibling was not.