In 1994, Daddy Dave and Daddy Bob prepared 5-year-old Elizabeth Wall for the first day of kindergarten in New Jersey, meeting with the principal in advance to ease her transition as the daughter of two gay men.
They never learned until years later how insensitively the school reacted to their unconventional family, according to Wall, now 20 and a sociology major at The College of Wooster in Ohio.
"They had never had gay parents before," Wall told ABCNews.com. "It's funny, after the principal met with them, he went to the faculty and said, 'Who wants to take her?'"
Fortunately one teacher, who later became a close friend, volunteered and took the little girl under her wing in the classroom, but for years Wall was careful about only telling close friends that she had two fathers.
"Obviously I was different and didn't have a mom," she said. "We are living in a world that treats our families differently. It can be isolating and challenging."
Of the 270,000 children living with same-sex parents, about 65,000 are adopted. Most, like other Americans, are in two-child families.
"It's amazing how many of us there are," said Wall, who is working this week as a counselor with the organization COLAGE, or Children of Lesbians And Gays Everywhere, at its Family Week in Provincetown, providing children of same-sex families with support.
20 Percent of Gay Couples Have Children Under 18
Just under one percent of all couples in the U.S. -- or 594,391 people -- identify themselves as gay, lesbian or transgender, and about 20 percent of them are raising children under the age of 18, according to the Williams Institute, an organization that advances sexual orientation law and public policy.
Having children is made possible through reproductive technology such as egg or sperm donation and surrogacy. Many, like Wall's parents, choose to adopt. About four percent of all adoptive parents are same-sex couples.
"Anecdotally, we are hearing a lot of stories about what is being called the 'gayby boom,' same-sex couples having children," said Naomi Goldberg, a public policy fellow at the Williams Institute.
"They are shattering the stereotypes that gay men don't want kids," she told ABCNews.com. "They want the same thing straight couples want."
Television personality Rosie O'Donnell first brought gay parenting to light in the mid-'90s and since then, same-sex families have gained growing acceptance in a predominantly heterosexual society.
Today, gay marriage is legal in six states. And for the first time in history, the 2010 census will include data from same-sex marriages, unions and partnerships, bringing gay families out of the demographic closet.
But families like the Walls say it's been a long, hard road to gain societal approval.
In 1989, at five days old, Elizabeth Wall was adopted by David Wall and Bob Houck (though Houck would not get legal custody until 1994) as part of the first major wave of children adopted by gay couples.
Prior to that, children who lived in same-sex households were from straight, divorced parents.
Children of Gay Parents Come of Age
"There were few 'out' models of gay and lesbian-headed families 20 years ago," said David Wall, registrar at Princeton Theological Seminary. "Many folks were still in the closet or only partially out. That has now totally changed."
Elizabeth Wall was born at the height of the AIDS crisis in New Jersey and was at risk for being a "boarder baby," according to David Wall. "No one wanted these kids."
Her biological mother died of the disease, and Elizabeth Wall hersellf tested positive for antibodies until she was 2.
At 12, she was reconnected with her biological family, finding she had a sister, uncle, aunts and cousins.
But as a child, her adoptive parents made a point of having female role models in her life -- grandmother and trusted family friends. "I didn't long for a mother," she said.
There was only one support group in New Jersey, and the family had to travel one to two hours to find another gay couple with a child.
"Each year, new things would come up, and she was educating the teachers and classmates, daily," said David Wall.
Forms -- from schools to doctors to insurance companies -- were the biggest issue for the couple.
Annoyed by Forms and Afraid to Travel
"People just didn't ever imagine our family configuration," David Wall said. "I was constantly crossing out mother and father, mom's phone, mom's work, etc., and putting parent or simply crossing out mother and putting in second father. Our box just simply didn't exist."
When their first family photo appeared in their church directory, conservative groups made derogatory remarks. Wall and Houck were afraid to travel for fear they would not be recognized as their daughter's parents and always carried her birth certificate.
But by the time Elizabeth Wall got to high school, she was greeted by an openly gay principal and found a friend from a similar same-sex family.
"Churches are much more open to gay young people coming out, and families like ours are more visible," David Wall said. "And people are no longer afraid to talk about our families."
Cathy Renna, a Washington, D.C., lesbian, and her partner have a 4-year-old daughter through artificial insemination. They often attend Rosie O'Donnell family cruises and hear discussions by older children about the challenges of having gay parents.
"I was trying to imagine when she was a teenager what she would say," said Renna. "Most of the kids on the panel were the product of hetero marriages and the parents came out. That's totally different than being brought into the world by a same-sex couple."
"This generation of kids growing up will look back and wonder what all the fuss was about," she told ABCNews.com. "This kid could not be more loved or more wanted."
Less research has been done on children in families headed by gay men, but data collected as part of the National Longitudinal Lesbian Family Study have shown few differences in psychosexual development, psychological adjustment and overall well-being.
"Boys seem to do as well as girls," said Dr. Nanette Gartrell, associate clinical professor of psychiatry at University of California, San Francisco and principal investigator in the 23-year study.
"Most offspring of same-sex parents are heterosexual as adults," she told ABCNews.com. "By the time our study kids were 10 years old, they demonstrated a sophisticated understanding of diversity and tolerance, and an appreciation of the destructive effects of discrimination."
Lesbian Daughters Have Double the Fun
Abby and Jenna Bergman of Los Angeles have two mothers: Natalie and Kim Bergman. The lesbian couple was married in British Columbia in 2008 and has been legally recognized in California while Proposition 8 is being challenged.
"Love makes a family," said Abby, who is 13. "I always grew up this way. I never realized anyone was different."
Though Jenna, 10, thinks it might be "kind of cool" to know what it's like to have a dad, she has friends and even a teacher with "two mommies."
The girls have uncles and a grandfather who have been a male presence in their lives. They also like making two presents on Mother's Day -- "double the fun," said Abby.
For the most part, their lives are not unlike their schoolmates', though every once in awhile they encounter ignorance and homophobia.
"Once at camp I remember talking to a kid and becoming rather close, but when I told him I had two moms, he avoided me for the rest of the week," said Abby. "He was afraid because his parents had said something to him."
Jenna, too, said when she was younger some of her classmates thought her family was "weird and didn't understand it."
The girls have been told by their mothers, "you can marry anyone you want, regardless of gender."
For Julien Goutierre, who is heterosexual, growing up in a same-sex family has expanded his view of relationships.
The 33-year-old health care worker grew up in Paris with a gay mother who introduced her partner to her son when he was 13.
"I preferred it be a girl than a man," he told ABCNews.com. "A woman would be less dominant."
Claire Elkins, an American, and Barbara Goutierre, who is French, married in Vancouver in 2003, and their son said their relationship has shaped his own character.
"I am very tolerant about gay people, and with my girlfriend I shared the housework, cleaning and doing all the dishes," said Julien Gouttiere. "In France, that's something men just don't do."
Meanwhile, Elizabeth Wall, who is also straight, agrees that being the daughter of a gay couple has made her more tolerant of others, no matter what their racial or religious background.
"It's given me a lot more confidence in my family and makes me a stronger person," she said.
Houck became her second legal parent after the ACLU took on their case, the second in the state, to challenge the adoption laws in New Jersey.
"It opened the door to others," said David Wall. "I worried if something happened to me that my brother would get Elizabeth instead of Bob."
Though they had been legal domestic partners since the early 1990s, Wall and Houck exchanged vows in a civil union at their church in 2007, and their daughter took part in the ceremony.
Today, Elizabeth Wall said life with her two fathers is no different than having a mother around. "Both are very open and emotional," she said.
And like any set of parents, one is more permissive than the other.
"When I scream, 'Daddy,' they know which one I want by the tone of my voice," she said. "There's a Dad who says 'no' to everything and so I know which Dad to go to if I want something."