Forget to leave off a "sarcasm" tag?
I don't think that the parents should be prosecuted. Let Mother Nature take care of her own, meaning fewer homo sapien for my children to compete with.
I always laugh when I read posts by libertarians who make noises to the effect that, "Why bother to stop carnal behavior in children-- its irrepressible!" You can always tell those who were raised by people who didn't love them.
A dog will eat cat feces from the litterbox. Its purely natural behavior, but most people don't care enough about their dog to train him to stop.