> Whereas with birth parents, we know that the mother wanted a child [...]
I can think of many situations where this wouldn't be the case. Poor women in states with restricted access to abortion (requiring multiple visits to a clinic that's hundreds of miles away for example); women trapped in controlling relationships where leaving could be physically risky; teens who get pregnant for socially immature reasons and end up not wanting the child.
I can think of many situations where this wouldn't be the case. Poor women in states with restricted access to abortion (requiring multiple visits to a clinic that's hundreds of miles away for example); women trapped in controlling relationships where leaving could be physically risky; teens who get pregnant for socially immature reasons and end up not wanting the child.