Days after my son was born, I was shuffling through our apartment in my postpartum uniform of mesh underwear, a fleece-lined flannel robe and slippers, when my wife, Sam, called me over to the kitchen table. “Look at this,” she said, turning her laptop toward me. I blinked away my exhaustion as the screen came into focus. Sam had received an invitation to join a Facebook group for families connected by one thing: the shared genes of a 6-foot-2, blue-eyed collegiate soccer player. Our sperm donor.

Cryobanks ask families to report live births for the purpose of maintaining accurate records, but when we excitedly revealed Quinn’s birth date, we didn’t realize we were alerting other parents to his existence. I felt like someone had ruptured our cozy cocoon and exposed us. “Ignore it,” I told Sam. “I’m not ready to face this.” That was three years ago.

I’ll confess that, during those first few months, we dabbled in a bit of light voyeurism, occasionally clicking on profile pictures of group members and debating whether any of their babies looked like Quinn. The science of fertility had gone where my emotions could not, complicating my accepted definition of family. “Birth mother” never translated to “real mother” for me and Sam, and our children were going to be exclusively ours regardless of whether they had my freckles or Sam’s green eyes. When Quinn was born, I couldn’t imagine someone else staking a claim to him, let alone a stranger.

Creating a family with donor sperm leaves much unknown. The fertility industry has always been preoccupied with privacy. The nation’s most popular sperm banks require donor offspring to reach age 18 before they’ll be granted access to any donor information. California Cryobank even warns on its website that parents who violate its privacy terms will jeopardize their children’s future of contacting the donor.

Wendy Kramer, founder and director of the Donor Sibling Registry, disagrees with this policy. She believes that it’s an innate human desire to want to know where we come from, and that it’s our responsibility as parents to guide our children on their journey. “You need to have ongoing conversations so that your kids know that curiosity is normal,” she said. Kramer created the registry nearly 20 years ago because her son — conceived using donor sperm — began asking about his dad when he was a toddler. Wendy helped him learn about his biological identity. “It’s not just about telling them,” she said. “It’s about getting over whatever fears you have as a parent to honor your child.”

In the age of easily available consumer DNA tests, there’s no shortage of shocking fertility stories: fertility fraud, contractually restricted contact and buried family secrets. A friend recently recommended a new podcast called “Sick” that features true stories of dozens of donor siblings who connected after discovering that the Indiana fertility doctor who treated their parents secretly used his own sperm. Sam and I are even watching a new fall drama called “Almost Family” on Fox, which fictionalizes the same tragic plot. Suddenly, it feels like donor sibling stories are ubiquitous and my kid is a pop culture oddity.

Before motherhood, Sam and I talked about donor contact, but it felt like an issue for later. We never discussed donor siblings. The truth was hard for me to fathom. Based on our cryobank’s loose limits, it was possible for our children to have 100 or more donor siblings.

Sam is now pregnant with our second child, conceived using that same tall soccer player. The inconvenient truth here is that our own children will be as genetically related to each other as they are to any siblings they meet on Facebook. I recently asked Sam whether I was being melodramatic back when I told her not to join the donor group. She shook her head. “He’s ours,” she said. “We worked so hard to get him.” She was right.

Sleepless in bed one night with my pregnant wife snoring softly beside me, I opened my laptop and searched for the Facebook group. I clicked on the profile of the administrator. Her kids had the same light blond hair but otherwise didn’t look like Quinn. “Babe,” I rolled toward Sam the next morning. “I found the Facebook group, and I think I should join.”

She nodded, and I clicked. I was quickly accepted, and I typed a brief introductory post. By that afternoon, I’d received many friendly comments, including a private message from a woman in Canada. She welcomed me to the group, then wrote: “Here’s the weird part,” and explained that she had read an article a few years back about LGBTQ families to follow on social media, which included mine and Sam’s. “We watched your son grow through your posts and always thought that he looked and acted like our son,” she went on. “I considered messaging you to see if you used the same donor but thought that would be weird.”

I clicked on her profile and felt like I was seeing pictures of Quinn laughing with strangers. We messaged back and forth, sharing our stories and initial reservations about joining the group, how we wanted to keep our boys all to ourselves, wanted our wives to know they were “real” moms. In the end, curiosity got both of us. “I don’t want to be the one who denies my kids the opportunity to make connections with their donor siblings,” she said.

Thousands of miles apart, raising boys who may or may not want to know each other in the future, we both came to the same conclusion: This is their journey, not ours.

The group, it turns out, is mostly posts from families looking for more sperm — our donor is no longer active — and talking about infant constipation and eczema. Our donor families are spread across the United States, Canada, Europe and as far as Australia. Many of them are two-mom couples, which gives me an unexpected space to swap stories of same-sex parenting and gives Quinn donor siblings with whom he will be able to relate on more than just a biological level.

Quinn is now an energetic, inquisitive toddler. He loves trains, trucks, buses and any other tripping hazard on wheels. He’s learning to count, so Sam and I often ask him how many moms he has. “One and two,” he says as he points to both of us.

This time I replied, “You don’t have a dad, right? You have a donor.”

He paused and walked to get his water cup off the table. His back to me, he said: “I don’t have a daddy. No daddy.”

My heart scrunched. “Do you like having two moms?” I asked in a hopeful, high-pitched voice.

“Yes,” he replied as he brought his cup to his lips.

“We love you,” I said.

He swallowed, looked at me and said, “Let’s play trains.”

Laura Leigh Abby is a writer, wife and mama living in New York’s Hudson Valley. She is the author of “2Brides2Be: A Same Sex Guide for the Modern Bride” and “The Rush,” an Amazon Kindle Single.

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