Paths accidentally cross five times within one donor family

One extended donor family, with members spread across 20 US states, has had five instances where individuals crossed paths. And those are just the ones they know about.

Despite what sperm banks tell parents, a single sperm donor's sperm can be handed out to scores of different families, sometimes resulting in hundreds of offspring. One fear is that these offspring will meet, be drawn to each other and develop relationships without knowing they are half-siblings. It can be jarring to find out that your best friend is actually your genetic half-brother. 

Below, I briefly recount five known instances of crossed paths within a single extended donor family. The sperm donor donated at four separate sperm banks located in two states. So far, 93 offspring have been linked to his donations, but there are probably more. Importantly, the offspring live all over the US — from Maryland to Texas to California — and these chance encounters have taken place nonetheless. 

Crossed Paths

Friends discover they used the same donor

They were already acquaintances — two lesbian couples living in the same area. When both couples were expecting at the same time, the conversation turned to the journey that got them there. That's when they realized they'd used the same donor. 

School chums and soccer mates find out they're half-sisters

The two girls were close friends, in the same grade at the same school and on the same soccer team. Their moms — four women in two couples — were side by side in the bleachers, cheering on their daughters during a game. They got to talking about their road to pregnancy and the sperm banks they'd used. Same bank, it turned out — and same donor. One minute earlier, the girls had just been childhood friends, but now they were half-sisters. The parents felt unsettled: what would this mean for their kids, for their families? 

Counsellors at the same summer camp

In early adulthood, one male and one female offspring worked at the same summer camp as camp counsellors. True, it wasn't the same summer. But after they met through DNA testing, they were surprised to find on Facebook that, despite being from different states, they had lots of mutual friends. Then they noticed they had both "liked" the same summer camp. That's when they figured out they'd both worked there and had both been invited to the same camp reunions.  

Students at the same university

Two female offspring ended up at the same university at the same time. One of the offspring is active in the donor family social network; the other is known to the group primarily through genetic testing. 

Same university, one a class mentor in a half-sibling's class

Two daughters from one family and a son from another attended the same university. They knew of each other prior to applying, but only learned about the coincidence after accepting. The older half-sister, completely by chance, became a mentor to her half-brother's class. 

This family's experience underscores how easy it is to encounter donor siblings without even knowing it. It's an important reminder to parents using donor gametes to always disclose to their children. 


Donor Sibling Registry


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