Question for you guys concerning foster children...

The biological father will stay the girl's father. He will also continue to invite himself as long as the girl is a baby or toddler.
Vlad won't become related to the girl.

Think of Vlad as the girl's legal guardian. He will become eligible to do the parenting interactions, get asked for advice occassionally by the girl (if free will is on) and the school might call him instead of the mother when a parenting chance card occurs. I haven't found a pattern to which parent/guardian is called. It seems to be random, so you'd best skill parenting on both Vlad and the mother.