As others have said if he doesn’t like the arrangement he can always cough up and put him in a nursery or send him to a childminder. I can’t see either of those options keeping other children quiet so that his son will be able to take naps.
He doesn’t know when he’s onto a good thing. Does he pay you the going rate for childcare? Does he pay you at all?
What was your favourite board game as a child?
New and unused skincare - where can I send this please?
It's official: Grandparents are good for children
how are schools handling students who memorize books but can't actually decode
