Mikayla Stern-Ellis and Emily Nappi, freshmen at Tulane University, said they met on Facebook while searching for potential roommates, and they remained in contact despite ending up with different roomies, the Tulane Hullabaloo, Tulane University's student newspaper, reported Wednesday.
The girls said they got to know one another and eventually discovered they both had Colombian sperm donor fathers.
"We've been telling people, 'Oh, there's a 25 percent chance we're sisters,'" Nappi said.
Heidi and Debra Stern-Ellis, Mikayla's parents, said the girls had a lot in common, leading them to suspect their daughter could have met her own half-sister.
"When she told us that they had talked a little bit and knew they both had a Colombian donor, Heidi and I said to ourselves, you know, we remember going through the donor list, and there [were] probably about 1,000 donors," Debra Stern-Ellis said. "We don't really remember any [other] Colombian donors, so when Mikayla came home for winter break, we were sitting on the couch and looking at Emily's picture and her picture, and I said to her, 'You should text her and ask her for the donor number.'"
The girls were shocked to discover they shared the same donor.
"For me Tulane just felt right, and this is one of the many things that proves I made the right decision," Mikayla Stern-Ellis said.
Debra Stern-Ellis said both girls are interested in acting and are appearing together in a production of "The Vagina Monologues." She said the donor listed theater as one of his interests on his profile.
"We thought [going to Tulane] she'd just find an education, but she found a sister," Debra Stern-Ellis said.
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