Mommy has a headache and needs to rest. She asks Caillou to look after Rosie while the two children color quietly. When Rosie starts scribbling on the wall, Caillou tries to take away her crayon, but Rosie starts crying and wakes Mommy up! It's not always easy being the big brother. Watches Rosie includes a ''Caillou Good Habits'' poster for parents to encourage their child to develop good habits, such as putting away their toys or brushing their teeth, over the course of one month.