To me there is a clear difference between children, and teens say 16+. It is both morally wrong and unnatural to be attracted to prepubescent children, and this is pedophilia. But basically, by definition puberty makes people become sexually attractive, and it's natural for adults to be attracted. Still morally wrong to act on those attractions unless you're in about the same stage of puberty or early adulthood. That's when we rely on a strong moral code and laws in society to protect youngsters who have recently gone through puberty. And hopefully even after the laws no longer apply, we have enough societal pressure to strongly discourage wide age gaps between sexual partners.

Pedophilic disorder is characterized by recurring, intense sexually arousing fantasies, urges, or behavior involving children (usually 13 years old or younger).