The age of two is significant for a child's motor, cognitive, and social development. At this age, the child walks, runs, begins to speak, stabilizes emotional ties, and starts to become autonomous. At the same time, the child experiences all sorts of emotions, with great intensity.Through situations taken from everyday life, the books in the Step by Step series put into words the experiences and emotions of very young children. They describe what children feel intensely in their relations with themselves, their families, and the world beyond. By encouraging youngsters to identify with Caillou, the books help parents to deal in a pleasant way with subjects that could otherwise become sources of frustration.The Step by Step series is an attempt to translate into books the inner life of a child and his varied and sometimes contradictory feelings. The universality of the situations described and the environment in which Caillou grows up portray youngsters' relation to the world around them and help them to assert their identity.

Children recognize themselves in the character of Caillou and in the situations he experiences, because his adventures and misadventures are those of all children.The books in this series were developed with the collaboration of child psychologist Francine Nadeau, M. Psych.