Thanks everyone! When I wrote my contract I assumed that if parents were off they would want to keep their kids home with them, but I guess that's not the case. I agree, wonderwiper that I don't have any basis to be resentful - it's still there though.
I love how the parents say, 'oh yeah i just though i would take a break today and do some shopping'. seriously??! you see your kid for 2 hours in the evening and on the weekend!!
oops... there's that resentment coming out again :-/...