Ashley Thomas (31) and Latoya Wimberly (29), from Philadelphia in the US, who have been besties since they were teenagers, only recently discovered that they have the same father, CNN reports.

Over the years, people have often pointed out how much they resemble each other. Both have gaps between their front teeth and high cheekbones. The two even fell pregnant at the same time by two brothers.

They discovered they were sisters when they shared a picture of Latoya’s engagement party on Facebook. Latoya’s dad, Kenneth, was in the picture too.

A friend of Ashley’s late mom commented that she had known Kenneth. This prompted the 29-year-old to dig deeper into her father’s past, Daily Mail reported.

After discovering her dad had briefly dated Ashley’s mother, Michelle, back in the day, Latoya asked her dad to take a DNA test. The result revealed that Ashley is indeed his daughter.

“I almost passed out,” Latoya says about the moment she found out that her best friend turns out to be her sister. “Then I immediately called Ashley.”

Although Ashley was happy to have been told who her biological father is, it came as a shock that it’s also her friend's dad, Good Morning America reports.

“The first few nights [after finding out] I couldn’t go to sleep,” the 31-year-old says. “I’m happy that she’s my sister but had some emotions that this guy I’ve been around this whole time, I never knew he was my father.”

Kenneth says his relationship with Ashley’s mother, Michelle, was brief and happened when they were teenagers. They didn’t keep in touch after they broke up and she never told him she was pregnant.

Sources: CNN, Daily Mail, Good Morning America