No one approves of welfare mothers, abusive parents, alcoholic parents or the myriad other pathologies that too many innocent children are subjected to.
However, those realities don't necessitate that we reject traditional family structures and offer a de facto embrace of homosexual parenting. Will Mary Cheney be a good mother? Could be. Does that mean we should silently accept or actively encourage this concept? No thanks.
I'll illustrate my point with two words, Rosie O'Donnell.
Rosie wouldn't be a good mother even if she was straight. Anyone with that amount of hate, straight or gay, will not be a good influence on a child.