(May 19) -- Mia Washington, of Dallas, gave birth 11 months ago to her sons Justin and Jordan. The boys, who were conceived naturally, were born just seven minutes apart -- but medical tests show they're half-brothers, not full brothers.

Washington, it turns out, had a fling with a man other than her partner and ended up conceiving a child with both men. DNA tests from Clear Diagnostics, a local lab, showed there is no chance the boys have the same father, according to Fox 4 in Dallas.

Fox 4 asked doctor Chris Dreiling how such a pregnancy could happen. If a woman releases more than one egg during ovulation and has sex with more than one man during that time, her eggs can be fertilized by different men, he said.

But Dreiling added that such cases are extremely rare.

Washington had the boys' DNA tested after noticing their facial features were different. Her fiance, James Harrison, who fathered one of the twins, has decided to forgive her and raise both children as his own. The identity of the other father hasn't been disclosed.

Washington told Fox 4 she takes responsibility for what she did.

"I'm trying to let everybody else know: Don't put yourself in my shoes, because it can hurt and it does hurt, but you still have to go on with life," she said.