Sitters' headaches are a common problem for people who take care of children, especially those who are not their own. The term is used to describe the stress and exhaustion that can come from having to constantly monitor and manage the behavior of young children. The crossword solution for this term is IMPS, which stands for Irritable, Moody, Peevish, and Stressed. These are all words that can be used to describe the feelings of a sitter who is dealing with a headache.