No, I'm going to say he deserves some flak for not thinking this one through. His wife suggested an incestuous threesome with her own SISTER and that didn't ring any alarm bells? AND they didn't use protection? As another poster said, that's fifty shades of fucked up.

No man with a working penis would ever turn down such a thing. It's basically a dream come true.

There are some things I'll never understand about guys...or girls for that matter.

Only if you are dating the ugly one!

A sensible man who thought with his big head and not his little one would turn it down straight away.

Until it becomes a NIGHTMARE.

she ain't doing her sister. do you even know what incest is?

Simply adopt the baby? Sweets, why the hell would OP adopt a kid who is his biological child? as for the wife? Yes, I’m certain that she’ll want to adopt her sister’s child. It’ll be like a vacation souvenir to remind her of that ‘magical night’

Simple: the kid's mother is not the father's legal wife, so he has no legal parental rights to the kid. In order to get legal parental rights, he would have to adopt the kid. Adopting the kid would also free him from having to pay child support to his sister-in-law. Since he mentions that his wife is "still not pregnant", that implies that getting pregnant is a goal for the couple, implying that they want kids. Adopting the kid would give the couple a kid, remove the burden of single-motherhood from the sister(again, assuming that the sister is single), and give the kid a set of stable (... relatively speaking) married parents. As far as the wife is concerned, the adopting the kid won't be any more or less a reminder of the trio's <i>complete idiocy</i> than seeing the kid every holiday at family reunions. Quite frankly, if the wife didn't want the risk of her husband impregnating her sister, she shouldn't have invited her sister into their bed in the first place. Alternately, OP needs to get a paternity test on the kid. If dear sister would f*ck her own brother-in-law, who know who else she's been f*cking?

Then you are friends with weird people!