Grandma has knit Caillou a wonderful sweater. He loves it and wears it every day even after it gets dirty! Finally, on a hot day, Caillou decides to take it off. When he accidentally leaves the sweater in the playground and goes home for the day, he worries something terrible has happened to it. Grandma will be so upset with him! When Mommy and Caillou return the next day to find the sweater is fine, Caillou vows to never wear it again. He decides to keep it in his drawer, nice and safe until Grandma explains its okay to wear the sweater its meant to be worn - just not everyday.