Updated

A Texas mother of twins got the shock of her life when doctors revealed that her 11-month-old boys do not have the same father.

Mia Washington decided to get some expert advice when she and her partner noticed that twins Justin and Jordan had different facial features.

Paternity tests then revealed what had happened — two eggs had been fertilized by two different sperm and there was a 99.99% chance the twins had different dads.

Doctors at the DNA lab in Dallas, Texas had never seen such a result.

Washington later admitted she had had an affair and got pregnant by two different men at the same time.

"Out of all people in America and of all people in the world, it had to happen to me, she told myfoxdfw.com. “I'm very shocked."

"It is very crazy. Most people don't believe it can happen, but it can,” Genny Thibodeaux, Clear Diagnostics President, told the news station.

When twins have two fathers, doctors call it heteropaternal superfecundation, according to myfoxdfw.com. It's so rare — there are only a handful of documented cases in the world.

Click here to read more from Sky News.