MSD

I don't know enough about psychology and phsyiology to form a 100% informed opinion on the subject, so I continue to accept the consensus of the medical community that sexual activity between children and adults is highly likely to cause irreversible developmental and psychological harm to those children. I can be more lenient of activity between children because they are not yet familiar with the concept of human sexuality and are not biologically ready to be sexual, and therefore are exploring and learning about themselves and others; in these situations, it is, as always, the duty of the parents to explain things to children in terms they can understand, and to prohibit activities for which they are not psychologically and biologically prepared. I would consider sexual curiosity and experimentation healthy in mid to late adolescence, and that seems to be when it begins for most.
This is 100% true, but someone who is sexually attracted to children has a responsibility to refrain from acting on it.