Jenny Rain, 44, grew up for part of her life with two dads. (Michael S. Williamson/The Washington Post)

When she was a child, Jenny Rain couldn’t help but wonder whether there was something wrong with her family. There were the jokes on late-night television. The sermons in church. The time those boys hurled slurs on the Virginia Beach boardwalk, her two dads strolling obliviously as she boiled inside.

As she grew older, it dawned on her that it would be up to people like her — the children of same-sex couples trying to forge families in a skeptical world — to show the United States just how normal her upbringing was. But she had no idea that her own situation would be part of the evidence considered by federal judges in their ruling on same-sex marriage.

As the Supreme Court prepares to hand down what may be a historic decision on whether gay couples have a constitutional right to marry, the children of these couples have been at the heart of the debate. Gay rights activists have turned old arguments on their heads, putting the more than 210,000 American children being raised in same-sex-couple households at the core of their closing arguments.

Advocates have seized on the words of Justice Anthony M. Kennedy, who in striking down the federal Defense of Marriage Act two years ago wrote that the law “humiliates tens of thousands of children” being raised by gay parents. Taking the cue, groups have put these children’s stories front and center in campaign ads, on rally stages and in legal briefs.

At the same time, opponents of same-sex marriage have tried to maintain their traditional approach of championing children’s rights. In their own briefs and publications, the opponents argue that children do best in households led by their biological parents. And opponents highlight the stories of children who recall their gay parents with pain and bitterness.

Jenny Rain with her two dads. Her biological father is George Gangloff, center, and his husband, Dencil White, is at left. Rain grew up for part of her life with her two fathers. Rain, 44, lives in Northeast Washington. (Family photo)

Rain, 44, a marketing consultant from Northeast Washington, said she recognizes the pain felt by some children of gay parents. But in her case, she concluded, it stemmed from the divorce of her biological parents and the stigma — not her father’s sexual orientation. Her father’s marriage to his partner of 37 years last year in Palm Springs, Calif., at which she was the sole guest, was a salve on all that, she said.

“You don’t think a simple piece of paper can further bond you as a family, because, let’s face it, we’d been operating as a family for 37 years,” said Rain, whose story was recounted as part of the legal briefs in the case. But “that paper gave us a validity that, in my heart and in my mind as the child of gay parents, stripped away the marginalization that we had been through for decades.”

Nearly 1 in 5 same-sex couples, and about 1 in 4 same-sex couples who are married, are raising children, according to the Williams Institute, a research organization at the University of California at Los Angeles that studies the gay and transgender population.

Some are the biological children of one parent from previous heterosexual relationships. Some are adopted or foster children, and others were conceived through sperm donors or other methods.

Leading medical organizations, including the American Academy for Pediatrics and the American Psychological Association, have endorsed same-sex marriage, citing studies showing that children raised by gay parents fare as well as their peers with different-sex parents.

But opponents of gay marriage say it is too soon to conclude anything definitive, because legal same-sex marriage is so new.

Backers of gay unions say there is real harm in taking a wait-and-see approach, because these families are facing difficulties. Many states bar unmarried people from adopting children jointly, meaning the adoption is granted to one parent or the other. Problems can even arise for parents who have been legally married, because their rights could dissolve upon crossing into a state that does not recognize their union.

The nation's highest court is hearing Obergefell v. Hodges, a case that examines whether same-sex couples have a constitutional right to marry. Here's what you need to know about the case that could make gay marriage legal across the nation. (Julie Percha/The Washington Post)

That has led many couples to take extraordinary steps in case of emergency. For instance, Danielle and Jennifer Hounshell were legally married, but when Jennifer gave birth to their first daughter, the couple decided to take precautionary measures. They had Danielle adopt the child as a second parent, even though Danielle was listed on her birth certificate.

Now, whenever they drive any distance from their home in Johnson City, Tenn., they carry a thick gray envelope containing their marriage certificate, adoption papers and birth certificates, just in case. If same-sex marriage becomes legal nationally, it will be a huge burden lifted, Jennifer said.

“For my kids, I don’t want them ever feeling oppressed, seeing that their parents aren’t welcome in society, or to get the idea that we are ‘less than’ and we shouldn’t be respected and we are disgusting,” she said. “On a personal level, it’s just relief and freedom — we can travel without our papers, finally.”

The idea that children are central to the debate over gay rights is not new, with critics over the years casting gays as deviants and even predators. In the past, gay rights groups did not aggressively press the issue. “We allowed, I think, the opponents of marriage to drive the conversation about children and families . . . from a vantage point of fear of the unknown,” said Emily Hecht-McGowan, director of public policy for the Family Equality Council.

But that changed over time, she said, with perhaps the biggest turning point coming after Kennedy’s opinion in the Defense of Marriage Act decision.

“The law in question makes it even more difficult for the children to understand the integrity and closeness of their own family and its concord with other families in their community and in their daily lives,” he wrote.

As the conversation has changed, opponents of same-sex marriage have taken a more nuanced stance on the matter of children: Allowing gays to marry harms children because it can cut them off from at least one biological parent. Same-sex marriage also elevates the desires of adults over the rights of children, opponents say.

Katy Faust, a blogger from Seattle, recalls a loving, if unorthodox, upbringing as the child of a gay mom in Portland, Ore. Social engagements revolved around her mother and her longtime partner’s soccer league and marimba band. Her father remained a strong presence in her life.

But as she grew older, she said, she began recalling aspects of her childhood with a “sense of loss” and a feeling that despite the warmth and stability of her mother’s home, her life would have been incomplete without her father.

That feeling — that both biological parents are necessary to grow up whole — solidified when she had her first child, she said.

“No child should grow up without a mother,” said Faust, who is a Christian but said her views on this issue do not grow out of her religious convictions. “It happens, but it’s awful, and we should be able to say how awful it is.”

Robert Oscar Lopez, another child of gay parents who is an outspoken critic of same-sex marriage, has said that some same-sex parenting can be a form of child abuse. Lopez, a professor at California State University at Northridge, said in an interview that he believes more children of gays feel the way he does but keep quiet out of a desire to protect their parents, whom they love despite their ambivalence.

“The majority of these kids have a median position,” Lopez said. “They want some sort of respect for the couple, but they don’t want to be forced to call someone a parent who is not their parent.”

Faust and Lopez also told their stories as part of legal briefs in the case before the Supreme Court.

Supporters of same-sex marriage counter that most of these unhappy stories arise not from the fact that the parents raising the children were gay but from other factors, such as the trauma of their biological parents’ divorce.

Some gay parents say they try to ensure that their children retain a connection to any biological parents who might be out of the picture — even when those parents are anonymous. For example, the Hounshells, whose daughters are 3 and 6 weeks, celebrated Father’s Day with a meal of jerk chicken, beef patties and coconut rice — an homage to their sperm donor’s Jamaican heritage.

“We call it ‘Donor Daddy Day,’ ” Jennifer Hounshell said.

Rain, the marketing consultant from Washington, takes issue with the notion that a mother has to be present to provide nurturing. Before her biological parents divorced when she was 6, she said, it was her father who changed diapers and threw hunks of meat and potatoes in the crockpot for dinner while her mother toiled at her studies and job.

Today, Rain said, she maintains close, positive relationships with her biological mother, biological father and two stepdads.

“People are seeing mom as a gender, thinking there’s some magic that’s going to automatically make them nurture a child,” she said. “I more firmly believe it’s the role that somebody adopts, not their gender, that is important here.”