Bellas Fat cat in Bay View has a private party room. It is an ice cream place, so I am not sure if they could provide a cake, but you could see. I know they have package plans, where you can get however many hot dogs or bugers or sandwiches or whatever for a set price. The room is large, so 4 people would certainly be ok. You can also decorate the room. They aren't any real activities provided but you could set up a game of you own. Good luck, you sound like a very devoted mother.