That said though, it's easy to imagine how quickly things could become problematic if some busybody decided they wanted to make trouble. You do not want CPS involved with your family - full stop.
I don't really know what the right thing to do is if you do have CPS show up - at first blush it seems like a "never talk to the police" type of situation where hypothetically the right play is to absolutely refuse to play ball and involve a lawyer immediately.
It's a whole can of worms to take that stand though. Do you just let Umbridge into your house and hope that the quick look around is enough to close the case? Or do you recognize you're dealing with an Umbridge and not take the chance?
That kind of tough call for parents probably does mean that the right play is to try to ensure your state has reasonable legislation about these sorts of things.
(what a drag!)