Sounds like my mom's BF's situation.

He and his wife divorced 10 years ago. He had this nagging feeling that the two youngest children were not his...and after some coaxing from my mother, he went to get paternity tests done. It was too obvious--the kids were pale skinned compared to their older siblings. [their mom and my mom's BF were dark skinned]

The paternity tests proved that he was not the father of the two children. He's being given back the 10 years of child support he had to pay.