Here are some lines. I need some help with the 3rd one.
もう子供にはかまうな <-- can't figure this one out
Somehow, I can't figure out how it fits into the context of the story. Basically, this was said by an outsider to a father after they all just found out that his daughter was doing compensated dating (enkou). And she was doing it apparently because the father was cheating, including engaging in enkou with a girl younger than his own daughter. And in general the parents didn't pay much attention to her.
So what does "kamau na" mean in this context? "Don't get involved with kids?" Doesn't seem to make much sense to me.