We could also make it anyone on the family tree, and RP it as if that person was the adopter regardless of where the adoptee actually lands. The succession mechanic is funny enough to make the exact placement on the tree not all that important. This should still be subject to the max two physical adoptees unless the family member agrees otherwise. This makes it easier to get on the tree as you only have to be liked by one family member, still leaves people two offspring slots if they want them, and doesn't make people accept and RP sons that their avatars would never adopt, but adoptions still mean something because there is some family member willing to take that avatar as a son.