It is not natural for a homosexual couple to have a child, as this would never happen in the natural world. As much as homosexual people may like this to be the case, it will never be and they should accept the reality they have chosen. To corrupt the mind of a child so fundamentally is just not fair. Children need to realize that only a heterosexual people can have children from a young age. Only traditional families should be able to adopt.
Traditional families are highly overrated. What is so fundamentally wrong with having just one mother, or two mothers, or just one father, or two fathers? Nothing...Unless you're homophobic, and your fear and bigotry shouldn't take precedent over the love and care a single parent or gay couple can give to a child. Studies have shown children raised by gay parents are raised just as well, if not better, than children raised by heterosexual parents. There's nothing about wanting to have sex with somebody of the same gender that prevents you from proper childcare. And single parents are equally adept at taking care of children - I speak both from experience and from research. Sometimes gay parents can be abusive. Sometimes single parents can be abusive. Sometimes heterosexual parents can be abusive. The amount of parents or sexuality of the parents isn't what can ruin childhoods, it's the morals of the parents, the kindness and tolerance of the parents, and to say gay/single parents are incapable of kindness, tolerance, and morals is unsupported and inaccurate.
No, not only traditional families should be able to adopt, because we cannot always legislate to the ideal. A child with no parents would rather have one parent than none. A child with no parents would rather have two mothers than no mother at all. Anyone who wants to offer a child a chance should have a chance to adopt.