A kid that grows up in a same-sex union will be even more messed-up than one in dysfunctional heterosexual families.
Link? I've read a fair amount that says there's no significant data that gay adoption screws up the kids.
Like it or not, youngsters learn by example and spend most of their semi-sentient years doing enormous amount of ingraining by imitating adults.
That's an argument not just against gay adoption, but against allowing any homosexual(s) to raise a child. There's no principled way to prevent gay parents from naturally having babies via 3rd parties, or from using artificial insemination or surrogates, so it seems patently absurd to me that the government should categorically deny gays from being able to adopt.
Again, where's the evidence that gay parents cause problems with childhood development? Gays are still humans, and there are all sorts of different parental arrangements in the animal kingdom. If a single parent of unknown sexual orientation can raise a child, why not gay parents? There's plenty of evidence that sexual orientation is not one of the qualities of parents that's imitated. Exhibit 1: Mary Cheney. (and OMG, she's pregnant! Don't know precisely how, and don't care. That's so cool... daughter of the VP having a baby to be raised presumably by herself and her lesbian partner!)
Would 1 mother and 1 father be the ideal? Sure.
I'm not so sure. I like (in theory) Heinlein's concept of a line marriage, though in most places that sort of arrangement would be a social nightmare for everyone involved. I wonder how much of society would end up in line-marriage type arrangements if infidelity wasn't (i.e. if society lost its perception that marriage is 1:1). I think it's a superior family model. More parents means there's more chance that some respectable father and mother figure(s) are in each child's life, and more adults in a family means less financial pressure, which is a major cause of domestic unrest and poor parenting. There's more oversight by more adults; a badly-behaving parent can be kicked out with much less impact than a traditional divorce, particularly since the badly-behaved parent is unlikely to have been very involved in any of the children's lives.
I always thought of RAH's group marriage descriptions as comic relief, like his nudity kick in some novels. He sure didn't practice group marriage in his own life (married serially to two different women, AFAIK).
Group "marriages" have been tried in this country and proven to be astounding failures, most imploding in a few short years. They don't go well with Western Civ and economically developed countries.
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As to why gay parents may have a detrimental effect on kiddos, look no further than how children develop. One of the most marked behaviors of children is imitating those around them, especially their parents. Seeing how the rates of mental disorders & communicable disease, and life expectancy are much worse for homo than they are for hetero folks; I think increasing the liklihood of such a behavior/lifestyle/whatever is detrimental to the child's development.
Like fistful said, children born to two lesbians are
their kids & gooberment ought to keep thier hands off, just as it ought to keep its hands off any parents who engage in lawful behavior that may increase the odds of negative outcomes with their kids. Adoption is an entirely different deal, however, with the gooberment having an obligation to do what is best for the kids.