If there are, we can't see them. The government tells us what kind of books and stuff we can and can't read. But to be honest, they probably don't know either.

[Or so she assumes. Not like the kids know the absolute dirty truth of things. Most of the adults don't either.]

You have to slice open the nape of their neck. That's the only place they can't regenerate from. Everywhere else is just a waste of time.