Don't Tell Mom the Babysitter's Dead (1991)

When a single mother (Concetta Tomei) goes away for the summer, the kids are at first delighted, but then they find out that Mom has hired the sitter from hell (Eda Reiss Merin) to stay with them. When the sitter dies of a sudden coronary they deposit the body at a mortuary, only to discover that all their summer-expense money was in her purse. The kids must find a way to survive the summer without mom or her money. This means actual work.