Caillou
Grandpa – Caillou's paternal grandfather. He takes Caillou on adventures, often going on walks and riding the bus throughout the town where they reside. In "Caillou's Hiding Place", he showed Caillou a hidden area inside a tree in the backyard. In the episode "Caillou Goes Camping", he and Caillou camp in the backyard. He is Daddy's father and loves to tell stories about when Calliou's father was a little boy. He wears a blue shirt. Voiced by George Morris.