Interestingly, the "working inhumane hours" trope was once valid -- but is no longer.
Nowadays, child actors on a commercial set cannot be asked to work longer than something like three hours per day. And not more than 45 minutes at a time (check union rules for precise information). The off-hours are scheduled for play, school, meals, snacks whatever. It's a rigid regime.
However, one of the guys I cast (as a senior citizen) had been a child actor from the thirties...and we became close friends. He recounted his experience as a child actor: yeah, it was long hours -- but it wasn't "inhumane" and it wasn't "abusive"; "We all worked long hours in those days".
And he was never exposed to "perversion".
Hollywood is a lot different today...
Two things that came out of the reformation of labour laws for child actors was that and the fact that the child is only allowed to have a moderate stipend from his earnings until he reaches 18 and nobody else can touch his earnings.
The third thing that came out of that was that it is mandated that they are supposed to get an education as well.