Caillou
Rosie (French name: Mousseline) – Caillou's lively younger sister who is a typical toddler. She is two years old. She always wants to take part in the same activities as Caillou. In later seasons of the series, she becomes more talkative and independent. She wears a blue dress, red socks and blue Mary Jane shoes. Rosie fights with Caillou for some reasons, but they still love each other. She appears to be the only family member with red hair. Rosie was first voiced by Brigid Tierney (1997-2000), then Jesse Vinet (2002-2010).