My brother, now 50, has been separated from his partner for several years and has 17 year old daughter by her.

Anyway, he is autistic: not severely so but sort of thing you say : obviously' in hindsight.

His autism has not hindered him with girls. He is good-looking and naturally exudes IDGAF because he genuinely doesn't!

Anyway, about 20 years he becomes good friends with this married guy who is banging this fugly single mom as a side chick. This affair apparently ends. My brother then develops a FWB arangement with this chick. Partly because she was all over him and his autism makes him not want to do what it takes to keep a hot chick- learn self-reliance and other stuff it takes to be a successful guy. Plus he's getting older and the cool young guy Schick ain't working no more.

She gets pregnant and they become a couple. All the while the other guy is coming round as he is now my brother's best friend.

When kid is 3, his partner says that she had been ' getting close' to his best friend again but it was only cuddling.

Brother gets depressed and it all goes pear-shaped until limping to a halt a couple of years later.

The trouble is that his ex is now bitter as he wasn't 'romantic' and saw relationship as a transaction to raise family. He's autistic ffs.

So he rarely sees the kid.

Should he take DNA test, if it was some random dude I wouldn't give a shit but he's my brother.

He's moping about over a kid I wouldn't be surprised wasn't even his.

He likes truth btw, that might be a deciding factor.

Advice please.