(UPI) A pair of Pennsylvania woman who have been best friends for 17 years said they were shocked to discover after all this time that they are biological sisters.

Ashley Thomas, 31, and Toya Wimberly, 29, said they met in sixth grade at Sulzberger Middle School in Philadelphia and the pair soon became inseparable.

The women said they would often be told they looked alike and would get asked if they were sisters, but they always laughed it off - until recently.

Thomas said she found out about 15 years ago that the man she knew as her dad was not her biological father, but her mother never told her the identity of her biological father before she died a few years later.

Thomas' late mother's best friend was recently scrolling Facebook and came upon pictures from Wimbery's engagement party. She spotted Wimberly's father, Kenneth Wimberly, in the photos and recognized him as someone who used to spend time with Thomas' mother.

Kenneth Wimberly said he remembered the women and the group soon started to suspect he might be Thomas' biological father. A DNA test was conducted and confirmed the suspicions.

Kenneth Wimberly said he was shocked by the news.

"I was hurt, but also happy to find out that this beautiful and successful young lady was my daughter," he told Newsweek.

Toya Wimberly said in a Facebook post that the revelation has only strengthened their bond.

"That's why we're so similar, that's why we look so alike, that's why we've been inseparable since the 6th grade," she wrote.

Copyright 2020 by United Press International