No because if he had sex it would still be his son. His gf/wife had sex with his brother

well clearly it's says he's a male... meaning his wife had sex with his brother.

idiot.

*facepalm* OP's gf/wife had a kid if OP's brother!

You are the most idiotic person on this website.

he is a guy and his wife slept with his brother

Is this FML REALLY that hard to figure out? I mean seriously, people. Sheesh. OP - Ouch. Divorce your wife and claim custody? You should probably talk to her first, though. Unless you found out by talking to her, in which case proceed to divorce.

how could he get custody of any kind over a kid that wasn't his to begin with? wouldn't the child have to stay with the wife or go to OP's brother?

The brother that didn't raise or support the kid for 8 years? I doubt the brother doesn't know it's his kid, and even if he didn't it shouldn't matter. OP raised the kid for 8 years, while his wife has proven that she's not the best example for the kid. Unless OP is himself unfit. You don't have to be blood related to get custody of a child, and in this case he's the mom's husband, and he IS blood related to him, just not directly. Point being, OP can fight for the kid. If he wants to, of course. Maybe he doesn't want anything to do with the kid now.

He's not necessarily a husband, he could just be her boyfriend. And he could fight for custody but it's going to be rather difficult.

Are you stupid? Read all the comments from 3!

His wife cheated on him; she slept with with his brother, and got knocked up. OP, FYL indeed.

nephew** and I'm guessing his brother had sex with his wife and he thought it was his kid, which turns out to be his brothers therefore it's his nephew rather than his son.

If they were identical twins, their DNA would be exact and there would be no way of telling who's child it was. Thank God this is not the case.

174- Nobody has the same exact DNA, not even identical twins. How do you think they identify twin babies who get mixed up?

"If the two alleged fathers are identical twins it is not possible to identify the biological father because identical twins have identical DNA profiles." Your case may be different because the paternity test also has the mother's DNA to consider. So, I believe I'm correct!

no your still not correct

There are some very subtle differences in identical twins' DNA, especially copy number variations. Now that this is settled, can we get back to pointing out the obvious to all the morons who still don't understand this FML?

Most normal family's don't need a DNA test to prove a child his theirs! But sometimes, crap happens!

hey I'm not a moron....it just took me a bit longer to understand this FML LOL! bit I get it now!!

Judging by the fact that the OP's name is Ben... I'm pretty sure he didn't sleep with anyone.