NEW YORK (CBSNewYork/AP) — Two women enrolled in a Columbia University writing class have found their own lives were a story better than fiction.

As 1010 WINS’ Gary Baumgarten reported, it turns out they are sisters born to the same teenage mother in the early 1980s and adopted by different families.

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Katy Olson grew up mostly in Florida and Iowa while Lizzie Valverde lived in New Jersey. Both moved to New York as adults and enrolled in Columbia’s School of General Studies.

When they were attending the school, Valverde thought her sister was dead, while Olson was looking for her missing sister.

But then, they discovered they were sisters during a writing class in January 2013.

Valverde was telling the story of her life, while Olson was across the table listening.

“A few of the details that she said matched up with things that I knew about her from doing my homework, and I had started looking for her family online,” Olson said.

Valverde looked at Olson thinking: “This girl is having a panic attack. What’s wrong?” At that point, Olson said to Valverde: “I think you’re my sister.”

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“When she followed up with a rapid fire of more detailed personal questions, like, ‘Were you given up for adoption in Tampa, Florida to a woman named Leslie? And I was like, ‘Whoa, whoa, whoa,’” Valverde said. “The room just kind of froze, and I said, ‘Is this real life?’”

Valverde had already found their mother, Leslie Parker, a few years earlier. CBS News’ Mark Albert spoke with her by phone from Rhode Island.

“And she didn’t believe in a higher power… but you absolutely have to believe in one now, because it’s basically a miracle,” Parker said.

Parker was just a teenager when she gave up the girls a year apart, Albert reported. Thirty-five years later, her voice still broke.

“I wanted to give them the best possible future they could have, and it wouldn’t have been with me. As sad as it is to give up your own children, but I felt that’s the best that I could give them is to let them know,” Parker said.

The 35-year-old Valverde will graduate on Monday with a degree in creative writing. Olson, 34, and Parker will be in attendance.

“A lot of sacrifices were made for me to be sitting where I am right now – the largest sacrifice conceivably ever,” Valverde said.

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