I haven't had any luck finding it so far.
Xander has a child/children (can't remember how many) with Faith, but she didn't want them or him so she leaves them. I think it was a boy, but with my memory, well I can't be sure. So he takes care of his child/children and along comes Spike. They get together.
Somewhere near the end Faith comes back with her boyfriend (might have been Riley) to say hi. Riley doesn't approve of two gay men being fathers and wants to make trouble, but Faith won't let him. They leave again.
I don't know which season or if it is a total AU.
Does anybody know this fic?