Join Caillou in this special Halloween collection! From choosing a costume to wear trick-or-treating to conquering his fear of bedroom monsters, these stories will encourage your preschooler to take on life?s small challenges. CAILLOU? is an award-winning television series about an inquisitive four-year-old whose world is filled with learning, fun, and imagination and inspires generations of preschool children to grow emotionally and explore the world around them.