Sonoma teen Tyler Sievers discovers 20 half-siblings

Tyler Sievers sent his DNA to, and got 20 half-siblings back.|

Growing up as an only child, Tyler Sievers was comfortable with solitude.

His mothers expected their son to occupy himself – and so Sievers became a creative and resourceful boy. For 18 years he lived happily as a party of one.

And then he sent his DNA to, and got 20 half-siblings back.

He was conceived in March of 1999, using donated sperm banked at Pacific Reproductive Services in San Francisco. The donor was selected by his mothers from hundreds of options, using data that profiled each man’s broad particulars. Age, height, weight, eye-color. ?Medical history, family history, hobbies and skills. Sievers’ moms made their choice and his biological mother was inseminated. On Dec. 23 of 1999, Tyler Hammill Sievers was born.

His mothers were always blunt about their son’s origins, explaining early on that his father was a donor. Sievers was curious in the absent way that kids are, and admits to imagining his father from time to time.

“I’ve always kind of known, they didn’t hide that from me, though I didn’t press for details like his name or where he lived.”

Mostly, Sievers didn’t really think the circumstances of his life were unique. It was just a life, after all, like anyone else. Even if he’d wanted to know the details of his conception, that information was locked down, unavailable. “My moms told me the selection was an anonymous process. There was a packet with all his information (except his name) and that’s how they chose him,” Sievers said. “I like that it was anonymous. Choosing a donor based on a physical photo feels kind of shallow.”

Sievers is tall, well over 6 feet. He’s thin, his face angular, the chin prominent and cleft. Small dimples bracket the corners of his mouth, and his smiling eyes are blue. He’s a sweet kid, soft-spoken and tender. Not the kind of guy prone to bravado.

Last fall, his biological mother suggested Sievers take an ancestry test, thinking it might be fun to fill in some blanks. “We wanted to know about my ethnicity, countries I’m from,” Sievers said.

In October, he deposited saliva in a test tube and sent it off to Then the North Bay fires broke out, and he forgot all about it. is a geneaology service that’s been around since the 1980s. It uses DNA extracted from saliva to build family trees. It’s peppy advertising campaign features customers finding their unique happy endings: “Holy crow! I’m related to George Washington!!” and “So I traded in my lederhosen for a kilt!” The service costs $99, and has sequenced the DNA of millions of people. With its huge pool of participants, Ancestry is able to link its customers to their relatives, and does so with 99 percent certainty. The process takes between four and six weeks, and results are delivered via email.

“We didn’t even know about the feature that links you to people you might be related to,” Sievers said, remembering the shock of his emailed results. From Ancestry’s analysis of Sievers saliva, a large number of “really close matches” were made and over 200 probable cousins found. Within days, a woman named Melody reached out to Sievers, sure that he was part of what she called their “donor cluster”: 20 people ages 13 to 24 on the East and West coasts with 99 percent probability of sibling ties. The quiet kid who’d grown up in a house on his own was suddenly part of an enormous family.

Sievers’ biological father went to college on the East Coast, and made regular donations to a sperm bank there for cash. When he moved to the West Coast for a graduate program, he continued the practice, no doubt aware that children would likely be produced with his DNA, but perhaps not fully fathoming how many. The 21 children who share his DNA profile are known only because of their participation with Ancestry. It is entirely possible, even likely, perhaps, that there are others out there. Many others.

Taylor was the first half-sibling Sievers talked to, and she gave him the names of the other 19. Jackson. Clayton. Leah. Taylor. Jade. Sarah. Danika… So many strangers, all related by blood.

“We all have blond hair,” Sievers said. “And the nose and the chin and the height. It’s weird to look at photos.”

So far, Heather is the only sibling he’s met face to face, at Peets in Sonoma during the Women’s March in January. “We talked for a couple of hours, and it was awkward. There isn’t a guidebook for me to know how to deal with this,” Sievers said. “She said she was really thrilled when she first found out and tried to talk to everyone at once, but then got overstimulated and took a step back. It put up a barrier for me, helped me realize I need to take it cautiously.”

Thanks to legwork done by his half-siblings, Seivers now knows who his biological father is. He knows that the man has a traditional family of his own, a couple of young kids and a wife. He knows he is educated, where he lives, what he looks like. Not long ago, the man wrote a letter meant for all his offspring, explaining his why’s and his what’s. For Sievers, that’s enough for right now.

“I haven’t reached out to him yet because I want that to be one of the final steps. It’s said that you don’t choose your family. But for me, that’s not true. All these half-siblings… it’s a family of choice.”

Meanwhile, there’s senior year to finish and college essays to write. “I never thought until a few months ago that anything about my childhood was interesting,” Sievers said. “It was college applications that made me consider that my family was unique.”

Sievers has a proclivity for mathematics and photography, as do many of his half-siblings. Brainy and reserved, he’s hoping to be admitted to the University of Washington. Will he follow in his father’s college footsteps and donate his own DNA? “I’m open to it, but I wouldn’t say it’s a priority. I’ve heard in the future we’re going to be able to adjust hereditary genes to control what our children look like. That doesn’t feel right. It’s better to accept people as they are. This has definitely opened my eyes to what modern technology can do. With one saliva sample, I rewrote my history. It was one of the best decisions I’ve made.”

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