Caillou's Missing Sock - S1.E45

Caillou's Mom brings up laundry to his room and he needs a pair of socks. He finds one, but not the other. He goes down to the basement to look in the washing machine. He's too short to reach the washing machine, so he goes up looking for a chair, but the doorknob breaks off the door. Daddy is around and he opens the door. They go down to look for the sock together, but it's not there. Mom closes the door again and they get stuck downstairs once again. They call Mom and she opens the door. Dad goes to fix the door and Mom shows Caillou the laundry basket. His sock was in there the whole time.