California woman discovers she has 29 siblings through ancestry site

A San Francisco woman made a surprising discovery after taking a DNA test.

For years, 41-year-old Shauna Harrison thought she was an only child who, for some reason, didn't share the same physical features as either of her parents. However, she recently discovered she does have relatives with whom she shares common traits — 29 siblings, in fact, and still counting.

When Harrison was 27 years old, she learned that her mother and father enlisted a sperm donor to conceive her.

"I had been asking a lot of questions about my health and blood type," Harrison, a fitness professional, told KGO. "Because of my background in public health, I wanted to find out if I am more susceptible to certain things."

The news from her parents convinced her to try 23andMe, a website founded in 2006 that requires users to submit their saliva in order to determine their ancestry and health status. There, Harrison learned that her biological father, who also lived in the Bay Area, was of Russian and Jewish background.

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Two years ago, Harrison logged back into her account when she learned that 23andMe had made several updates. It was then that she received a message from one of her newfound siblings, who informed her they share the same father. Then, eight other siblings came forward. In a little over two years, that number ballooned.

"Just about a month ago, there were three new siblings within two weeks," she said.

The ages of all 30 children range from 24 to 41, with Harrison being the third oldest.

"It's a very weird — is the only word I can come up with — feeling when you meet because you know you share DNA with them," Harrison told CNN in another interview. "We bond in a very different way."

Some of the siblings knew each other before they realized they were related. Several were able to get in touch with their biological dad who, Harrison said, "wanted to father a lot of children."

Since the revelation, a few of the brothers and sisters have kept in touch through Facebook — one even created a welcome packet in the event they locate more siblings.