I agree with what Amos said about a possible genetic factor along with other factors being the cause. It's also been my experience that almost always, it is the youngest child that becomes or is a homosexual. Not always, but in most of the homosexuals I have known.

I disagree that homosexual marriage is a civil rights issue. They have the same right to marry as everyone else. They are demanding a change in the rules. But unless it is scientifically possible that the union can produce an offspring, then it cannot be marriage. I'm not going to split hairs and talk about geriatric marriages and other such factors that preclude making babies. The sexes must be opposite or it cannot be marriage.