How does it feel to be the biological parent of your sister's child or the aunt of the children you birthed? Americans are finding out.

(Illustration: Michael Willer)

Jodie and Shannon are sisters through adoption. Both have husbands and children and busy lives of their own. But in the course of building their families, the two found themselves leaning on each other in some unusual ways. “She’s an egg-making machine,” Jodie told me, somewhat admiringly, of her sister Shannon. “I, on the other hand, am an incubator.”

Jodie’s son was conceived using one of Shannon’s eggs. And Shannon’s twin girls were carried in Jodie’s womb. In case you have a hard time figuring out how all of these people are related to each other, welcome to the future of family and reproduction.

Here is the full story: Several years ago, when Jodie was in her late 30s, she was having trouble getting pregnant. “I apparently don’t make eggs,” Jodie explained. Shannon was then in her late 20s and single. So Jodie asked her: Could you spare some of your eggs? “I was a bit surprised,” said Shannon. “But I would have given her a kidney if she’d needed one.”

Soon after, doctors created embryos from Shannon’s eggs and the sperm of Jodie’s husband, Paul. Jodie got pregnant on her first round of IVF, and, in April of 2002, she gave birth to her son, Josh (some names have been changed). The sisters moved on with their lives in their respective cities.

They originally became family through parental re-marriage and adoption, so why not make another kind of family through fertility science?

Several years after Josh’s birth, Shannon and her husband, Eric, began trying to start their own family. But as it turned out, Shannon’s body could not support a pregnancy. That’s when Jodie stepped in and said she “had a womb to rent,” as she put it: She wanted to take on the pregnancy. Shannon and Eric were hesitant to say yes, but Jodie wouldn’t have it any other way. “I owed her,” she said with a laugh.

So Jodie became a surrogate (specifically, a “gestational carrier,” someone who does not provide an egg), pregnant with twins. In the photo album of their birth is a picture of Jodie in the delivery room as Eric, her brother-in-law, cuts the umbilical cords—two snips that effectively severed Jodie’s maternal connection to the two girls she had carried to term and birthed. It was the moment Jodie became an aunt. “This,” Jodie’s husband, Paul, said, “is what family does for family.”

Of course, for most people, for most of history, this is not what family has done for family. But assisted reproductive technology, or ART, is rapidly upending former notions of family and parenthood. Everyone today knows someone who has used ART to have a child. More than 65,000 babies were born through ART in 2012 alone. Added to this are ever more diverse family arrangements: same-sex couples, interracial couples, single parents, transgender parents, grandparents who take on parenting responsibilities, and adopted children. In our family structures and reproductive technology, we are in a futuristic age. But where are we culturally and mentally?

The interplay of technology and human reproduction has always been controversial. When artificial insemination was first the subject of medical literature over a century ago, the procedure was widely viewed as scandalous. Only after decades did opinions begin to soften. In 1964, Georgia became the first state to legally treat children who were conceived with donor sperm as the offspring of their mother and non-biological father, as long as both the husband and wife consented. Then, in the decades that followed, came sperm banks, “test tube babies,” IVF surrogacy, and anonymous egg donation. Today, preimplantation genetic screening (PGS) even allows parents to identify potential genetic defects in embryos, a technology that many fear places us one step closer to condoning “designer babies.” While PGS is not yet being used to select for things like intelligence, athletic prowess, or hair color, it one day could be.

Not all states permit each of these procedures. Other fertility breakthroughs are banned at the federal level. For instance, in 2001, the Food and Drug Administration put the kibosh on a technology that was being used to combine the DNA of three parents to produce a baby through IVF.

Reproductive ethics can seem distant once you meet the real people. Last summer, I visited Shannon and her twins, Jessica and Tessa, age five, in Potomac, Maryland. We rode in a car after a group play date in the park, and “Let It Go” from Frozen played on the car’s sound system. Every few seconds, Tessa, with ringlets of dark hair just like Shannon’s, would turn around to peek at me from behind her car seat’s head rest and flash me a secretive smile. The only remarkable factor about this otherwise ordinary drive was when the girls showed off how aware they were of their unusual family histories. Shannon is proud of how she and Jodie helped each other to have babies, and her daughters know the stories well.

“What did I do for Aunt Jodie?” Shannon called from the front seat.

“You gave her eggs,” both girls shouted in unison from the back.

“Why did I do that?” asked Shannon.

“Because she’s your sister and because you love her,” answered Jessica.

“Why do you think she helped us?”

“Because she is your sister and she loves you,” both girls said.

They’ve even been taught the biology.

“How did they make the embryo?” I asked, referring to Josh’s birth.

“With Uncle Paul’s sperm,” said Jessica.

“And my mom’s eggs,” said Tessa.

Much of this would be news to Josh. He knows that his mom carried his aunt’s twins—he was seven years old during that pregnancy—but Jodie has yet to tell him that he’s the biological product of his dad and Shannon. When I reached Jodie, who lives in Cleveland, by phone, to ask more about this, she freely admitted that the five-year-old twins know more about Josh’s birth than Josh. “Yeah, they’re ahead of their 12-year-old cousin, who’s oblivious and uninterested,” she said. Jodie said that Josh would have been confused about his genetic origins if he had been told when he was a young child. “He’d seen pictures of me pregnant, and I didn’t want him to think that I wasn’t his mom,” she said. “And as he got older, it was just never something we talked about.”

This is common among mothers who are recipients of eggs, according to Jean Benward, a licensed clinical social worker in Northern California who specializes in third-party reproduction. “They’re really quite afraid of the cultural myth that the child will turn to them and say, ‘You’re not my mother,’” she said. “This doesn’t happen.”

Many families intend to tell their children about their genetic origins at a certain age (as Jodie says she plans to do when Josh has “had a good sex education class”), yet as the years pass, and it doesn’t feel “right” to disclose it, the parents never do. Jodie says she feels Josh’s genetic history is almost irrelevant. “I forget about it so often. It’s just something that happened 13 years ago,” Jodie told me. “And it doesn’t really matter.”

In our family structures and reproductive technology, we live in a futuristic age. But where are we culturally and mentally?

But doesn’t it? No law gives Josh the right to learn about his genetic background, but veterans of assisted reproductive technology caution that the longer it takes for him to find out the true family narrative, the more shocking he might find the news. That the twins he thinks of as non-blood-related cousins are technically his half-siblings (something the girls have yet to piece together) is surely something he would like to know.

Michelle McGowan, a bioethicist at Pennsylvania State University, has observed that the psychological and ethical conundrums surrounding new types of family formations are causing us to retrace many of the steps taken decades ago with adoption. Much of what once was viewed as best for adoptive families has since been reconsidered. Fifty years ago, families often kept a child in the dark about having been adopted, revealing the truth only much later, if at all. Children who wanted to meet their biological parents were often discouraged and stonewalled. All of that has changed since the 1970s, when an adoption reform movement began to make the process more open.

When it comes to sibling egg donation or surrogacy of the sort undertaken by Jodie and Shannon, the emotional repercussions are still uncertain. One small study of mothers who received eggs from either their sister or sister-in- law found that the majority of recipient mothers felt that they and the donor had kept their “social roles” within the family (as opposed to their genetic roles), meaning that the intended mother took the role of mother, and the genetic mother took the role of aunt. But only nine mothers were in the sample.

Shannon and Jodie seem content and as close as ever, having so far avoided the major pitfalls (family battles, medical problems, financial troubles) that can come with arrangements such as theirs. Neither of them stakes any maternal claim over the other’s offspring. “Once I gave those eggs away, they weren’t really a part of me,” said Shannon about her nephew, her biological son. “It was kind of like giving blood.” Jodie, likewise, doesn’t think she’s bound to the twins in any unusual way, except that “I still blame them for the spare tire in my midsection.”

Still, because surrogacy and egg donation are such fraught processes, fertility doctors and clinics require that psychologists and lawyers be involved in each case. Egg donors and surrogates go through extensive medical and psychological testing, and the intended parents and donor or surrogate are required to have separate legal representation. Even with these failsafes in place, things can easily take a dark turn. For example, Jodie originally agreed to allow prenatal testing for genetic disorders, but when it came time, she refused, reasoning that she had no intention of terminating the pregnancy under any circumstances. “My husband’s completely against abortion,” she told me. How would things have gone had an abnormality later presented itself? Even the most thought-out contracts have their limits.

The American Society for Reproductive Medicine is only beginning to explore the ethics and implications of using family members as gamete donors or surrogates. In a 2012 report, it asked, “What are the consequences of the unusual resulting relationships on the donor or surrogate, donor-conceived persons, and rest of the family? What are the consequences of the creation of new genetic relationships that would be otherwise impossible?” As for answers, we have no idea.

Oddly enough, the fact that Jodie and Shannon are sisters through adoption may have made the entire process more natural to them. They originally became family through parental remarriage and adoption, so why not make another kind of family through fertility science?

At Shannon’s house, I got a chance to talk to her husband, Eric, a gastroenterologist who is accustomed to thinking in terms of biology. He’d come home after a long day of seeing patients, and Jessica and Tessa gleefully tackled him to the ground. Later, over a dinner of re-heated Chinese food, Eric admitted that Shannon’s egg donation years ago had initially made him uncomfortable. “I couldn’t get my head around that this was going to be biologically your baby,” he said to Shannon. But his feelings have since changed. “I learned a lot from all this,” he said. “What’s a family is who declares themselves a family.”

Submit your response to this story to letters@psmag.com. If you would like us to consider your letter for publication, please include your name, city, and state. Letters may be edited for length and clarity, and may be published in any medium.

For more from Pacific Standard on the science of society, and to support our work, sign up for our email newsletter and subscribe to our bimonthly magazine, where this piece originally appeared. Digital editions are available in the App Store (iPad) and on Zinio (Android, iPad, PC/MAC, iPhone, and Win8), Amazon, and Google Play (Android).