And I don't believe that children are innocent. In fact, no one seriously believes that. Just go to a playground and watch the kids playing in the sandbox! The romantic notion of the sweet child is simply the parents projecting their own wishes.
Sometimes you take a job for the money, sometimes you take it for the location, sometimes you take it for the script; there are just a number of reasons, and ultimately what you see is the whole landscape of it. But I can tell you from behind the scenes - that's what it is, as an actor.
The thing that teases the mind over and over for years, and at last gets itself put down rightly on paper whether little or great, it belongs to Literature.