Yes
If you didn't contest it, you should be receiving a custody order from the court. If you did not, request one.
Well you can take the matter to court. or you could just dissown your mother.
The law is determined by the place that you live.
If the question is an incriminating one then absolutely not. Example: Did you break the window next door? If the question isn't incriminating then yes. Example: Did you see where the robber ran?