I'm wondering how it works with our kids on the cruise - they are 7, 9 and 11 - we are going on the Disney Dream 3 night cruise in Feb (first time disney cruise, first time cruise!). I understand that there are snacks and ice cream and stuff at Flo's cafe by the pools that are included. Can the kids go and get something themselves or do they have to have a parent with them? how does that work?