Isn't this a bit like wanting a kitten to stay a kitten?
I don't know about this. I think my thought on this is very much like Laozi's.
As some of you may know, my wife is pregnant. Early on she asked me what we would do if the child wasn't... normal.
First, there are ways to find out early and then the parents(ok the mother but that's another debate...) can decide to abort or not and then to give it up for adoption or not.
Personnally and completely selfishly, I said abortion would be better for everyone including the child. My wife opted for adoption as for her, no matter how screwed up a baby is born, he/she still has a right to live a life. But since she has already delt with children with heavy dissabilities like this, she would never want to raise one of her own.
For me, and excuse me if this sounds horrible, any human born that can never attain a certain level of autonomy in society should be immediately put to rest.
But apparently, when your child is born everything changes. So we still really don't know what we would do.