A picture of the writer's sister-in-law, her wife, and their two children (Jack and Beatrix) during last year's Portsmouth (NH) Pride festival.

The dynamics of what constitutes the American family is rapidly changing. According to a 2014 PEW study, less than half—46 percent, to be exact—of children younger than 18 years old are living in a home with “married heterosexual parents in their first marriage.”

And it’s not just that adults are waiting longer and until they’re farther into their careers to conceive: PEW reported a year later that 16 percent of children live in ‘blended families’ (e.g. a household with a stepparent or a stepsibling); in the same study, it also announced that while seven percent of kids live with cohabiting parents, some estimates expect that rate could jump to nearly 40 percent by the time that child becomes a teenager.

But one of the most interesting elements born of these PEW deep-dives into the rapidly shifting American family is that 34 percent of kids are living with an unmarried—and often single—parent. Since there isn’t much data, though, to substantiate any concrete research on children born of same-sex parents—for example, PEW found that less than 130,000 U.S. couples are raising children under the age of 18—the institute folded in and included those percentages in this fascinating study of family culture.

Of course, the increasing number of children born to same-sex couples will clearly be a focal point of examination when the 2020 census is conducted. Early last year, Alexa Tsoulis-Reay of New York Magazine spoke to two women—Kate Elazegui and Emily Kehe—who decided to undergo pregnancy at the same time. The two each had boys (using the same donor), and the piece—including a recent follow-up after the couple’s first-birthday celebration—is an illuminating look at how subsequent generations will view familial relationships. Norman Rockwell’s depictions of suburban lifestyles will look quaint in the following decades, and Tsoulis-Reay’s touching and thoughtful piece is a perfect accompaniment to this Valentine’s Day.

KATE: Your maternal instinct is to take care of the baby you gave birth to. It’s definitely a challenge to bond with them both. Intellectually, we have to remind ourselves that there’s another baby. Of course I love Reid, but I’m getting a lot more time with Eddie because I’m breast-feeding him. So what happens is you’re bonding with the baby you delivered because you have to, and then you look over and remember that there’s another one. You have to remind yourself this is your son, too. That was always my fear. Because having a baby at the same time was not going to allow for the same bonding time for both parents with each baby. I think we expected to have a month to spend with Reid and then by the time mine came we’d spend time with Eddie. I do hope that this dissipates but you have to fight against the favoritism that you start to feel. Actually, that’s not the right word. It’s not a favorite. You are just partial to one because your job was to carry it for nine months. For me personally it’s really hard taking care of two babies. So I don’t get enough time with Reid.

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