Dennis Sidoti and Richard Silver were both born in New York. Both sing. Both worked in human resources before retiring. Their commonalities seem innocuous at first, just like any two people meandering the streets of New York minding their business. They probably passed each other plenty of times without realizing it.

But, as it turns out, they're brothers.

They'd never have known it had it not been for one of those ubiquitous at-home DNA test kits.

Everyone takes risks when using genealogical services – you're shipping your DNA somewhere, after all. It's a psychological risk, too, to uncover an unknown truth. But for some families, these DNA tests are revealing scandalous secrets that were kept from the rest of the family, often in the form of a child.

Before you send off your results, mental health professionals suggest considering the consequences and preparing for potentially life-altering news.

"In life, we often cannot prepare ourselves for how we will react to unexpected change," says Maryanne Fisher, a psychology professor at St. Mary's University in Canada, "but I think with these services, we can by asking about the intention to use them, and what we are prepared to do − and feel − if unexpected results are provided."

'This was all a shock'

Stories like Sidoti and Silver's long-lost brotherhood aren't all that uncommon, though neither Ancestry nor 23&Me keeps a record of such data. But 23&Me has an entire support page aimed at those encountering unexpected DNA results, and the hashtag #ancestrydnadrama has 1.5 million views on TikTok.

Sidoti, 68, added his DNA to Ancestry a little more than five years ago when his wife's family started digging into it – not knowing Silver had done the same. No one else in Sidoti's family had tried it before. On Feb. 23, 2018, he got the life-changing result: He had another brother – and a full brother at that, who can banter with him. Joke with him. Hidden from him for decades. How?

These women found out they were siblingsThen, they found hundreds more. It has taken a toll.

Call it an East Side Story: A young Jewish woman was in love with an Italian Catholic, and they found themselves expecting a child. But they couldn't get married because it would've been a frowned-upon, inter-religious marriage.

"My expectation, everything I can think of, is that she was given a choice of not having the child because it would have affected her family in a negative way, her in a negative way," Silver, 79, says. Their mother was placed in a home in Brooklyn to give birth to a child that Silver's parents would eventually adopt.

His biological parents ultimately skirted social norms, got married and had six more children: three more boys, including Dennis Sidoti, and three girls.

'I was feeling like an orphan'

Tracey Humphries, too, discovered a family secret through a genealogical service after both her parents died: The man she believed to be her father wasn't actually her biological dad.

The 58-year-old senior payroll consultant met her birth father for the first time last month after she discovered the truth.

"I was feeling like an orphan for years after 2013, and here I'm not," she says. "It's been something."

She had never questioned her upbringing other than wondering why she didn't look like her dad at all. But when she met her biological father all that changed.

"It was just unbelievable that I was looking at somebody that I look like," the Lakeland, Florida, resident says. "Because I knew I look like my mother, but I look like somebody else, too."

What happens when you 'unearth family secrets'

Happy family reunions like these certainly paint a rosy family portrait.

"For people who have small families but always desired a larger one, or who have few remaining relatives, it might open up new and wanted experiences," Fisher says.

And for some families, these discoveries could even be life-saving.

"It may allow for sharing of health news that could lead one to get tested for a predisposition, for example," she adds.

But experts agree that it's critical that anyone taking these tests be prepared for the alternative.

"For people with curiosities about their ethnicity and family backgrounds, these sites can provide some connection to a culture they may have felt disconnected from," adds Loree Johnson, licensed marriage and family therapist. "However, these sites can also unearth family secrets that contribute to a sense of betrayal, undermining family connections and closeness as individuals discover that they are not biologically related to an individual despite being led to believe so."

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'You and I are a lot alike'

Sidoti and Silver met for the first time some years back in Rhode Island; Silver has since met more of his siblings.

"It was a seamless meeting," Silver, of Asheville, North Carolina, says. "It was like it had always been. It didn't feel at all strange. It was very comfortable. Not like meeting someone you've never met before."

Today, they Zoom, email and text. They're hoping to get together again soon, perhaps with more barbs back and forth like this:

Sidoti: "We're really comfortable with each other and we actually like each other."

Silver: "Which is great, because I don't like that many people."

Sidoti: "The more I talk to you, Richard, the more I realize you and I are a lot alike."

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