Julia Tinetti and Cassandra Madison were both adopted from the Dominican Republic, and met working together in Connecticut
Cassandra Madison and Julia Tinetti
Cassandra Madison and Julia Tinetti
| Credit: Courtesy of Cassandra Madison and Julia Tinetti

A pair of coworkers whose many similarities helped them form a fast friendship were surprised to learn recently that their "twin" nicknames for one another were quite accurate, considering they're actually biological sisters.

Julia Tinetti, 31, and Cassandra Madison, 32, first met in 2013 as coworkers at the Russian Lady Bar in New Haven, Connecticut, Madison explained on Facebook.

For more on Julia and Cassandra's story, listen below to the episode of PEOPLE Every Day!

They had plenty in common, including matching Dominican Republic flag tattoos as a tribute to the country they'd each been adopted from, and soon struck up a close friendship.

"We become friends, start wearing matching clothes, having a blast together and telling everyone, 'We're sisters,'" Madison wrote.

A resemblance between the two inspired them to compare adoption papers, but the documents didn't match up, according to Good Morning America.

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Still, the women remained convinced they had some sort of connection, and kept in touch when Madison moved to Virginia in 2015, they told GMA.

Their case finally cracked open after a 23andMe DNA test led Madison to her biological father, whom she flew to visit in the Dominican Republic. Upon arrival, she learned that she had six biological siblings — including one sister who'd also been given up for adoption as a baby, according to the outlet.

A DNA test that Madison encouraged Tinetti to take eventually confirmed the news: they were, in fact, sisters.

"Fast forward to 2021 and I ask my dad if he gave up another baby he says yes! I'm buggin out, omg there's one more sibling!!!" Madison wrote on Facebook. "I jump in my car last minute and drove to CT to get [Tinetti] to do 23andme and the results came back yesterday."

"WE ARE SISTERS!" she wrote. "Same mom, same dad ! Just two girls who happen to work together find out they're sisters. I love you twin!"

According to GMA, the women believe that Tinetti's adoption papers were mixed up with those of her childhood friend Molly Sapadin, which would explain why Tinetti and Madison's papers did not match up when they first checked.

"[I'm] still processing the magnitude of the situation," Tinetti told the outlet. "This is the type of thing you see on TV. Finding my biological family just wasn't a thing for me. I grew up with a great family, so I just kind of left it to what it was."

Madison, meanwhile, said it's been a relief to finally reconnect with her long-lost family.

"For me, it's always been, 'I'm going to find these people if it's the last thing I do,'" she said. "I was going to die trying."