Before you refuse to babysit altogether, or even get upset over what your sister pays you, think about how frequently you’re asked to babysit and whether your sister ever does favors for you. I’ve always asked one of my sisters to do evening babysitting, and I’ve never paid them. I also don’t charge them when they need to borrow my van, need my husband to help fix their plumbing or put up paneling, or any of the other favors they ask me or my husband to do. Of course, I never asked them to babysit every week or even every month.