Girls need female role models if they are to fulfill their biological destiny of becoming wives, homemakers, and mothers. They learn from those female role models how to keep a house, how to cook, how to dress, how to shop for appropriate clothing, and how to carry a fetus for nine months and go through childbirth (and breast feeding) A girl who has a "mother" who is, in fact, a male, is at a distinct disadvantage in learning and mastering these elemental skills. True, men can cook, men can shop, men can keep a house, but they cannot do it with the insight that women can. It is well established that the brains of males and females are wired differently, with females being superior at multi-tasking, precisely the innate ability that homemaking and motherhood requires. Try as you might, you cannot endow a male "mother" with the ability to be a real mother. Does this fact impact society as a whole? Of course it does. "Mothers" who don't know how to be mothers raise young women who are not equipped to do what they are biologically foreordained to do. That is not a promising prospect for society. If you want to claim that this is a matter of small moment, please explain why females are physically and mentally provisioned to accomplish some critically important roles in life while men are not. Accepting your position is the equivalent of claiming that there are no physical/mental differences between men and women.
My job is, I believe, much less demanding than yours. If you are to argue that considerations of child welfare make gay marriage inadvisable, you will have to find cogent arguments, and those arguments must include an explanation of how the existing children of homosexual parents, with or without partners, would be harmed by allowing their parents to marry the people they love. That is a very hard argument to make. It has not happened yet. Limited comprehension is not an asset here.
