I don't trust the APA at all. I've been involved with them all my life, skimmed through several of their books (my father is a psychologist, so we have quite a diverse collection of books on psychology). They are very corrupt and literally are run by homosexuals. In fact, many people become psychologists in an attempt to solve their own psychological problems.
Because the love the child needs comes from two parents; the father and the mother. The love the mother provides is different than what the father provides because of hormonal and sexual differences. If, for instance, you had two mothers, they're both going to be very sympathetic towards the child instead of disciplining him, so the child ends up getting away with wrongdoings. Meanwhile, if a child is raised by two fathers, he is constantly disciplined, and so fears taking risks on account of punishment. The list goes on.
So know you're saying all women are sympathetic and linient, and all males are tough and disciplied. I know many people who parents are opposite, I know many whose parents are both one or the other.
I was just thinking the same thing. My mother was much stricter than my dad. And already I can tell my wife will be the disciplinarian in my family. In fact, I still remember how to say "No!" in daddy-dialect: "Go ask your mother."