Caillou is nearing completion of the beautiful castle he's quietly building in the living room when little sister Rosie stumbles right into his building block masterpiece. Absolutely furious that his castle has been destroyed, Caillou yells at Rosie, who starts to cry. Mommy comes into the room and, after carefully listening to Caillou, calmly explains that, while what Rosie did is clearly very annoying, she's just a little girl who didn't realize what she was doing. The Big Dipper series is designed to help children choose the best path to follow to enrich their lives and to help them navigate the ups and downs of emotional development. With Mommy's help, Caillou takes his first steps toward tolerance and learning to compromise.