Rainbow Valley shifts focus to the children of the Blythe family and their neighbors in the small community of Glen St. Mary. The story follows their friendships, adventures, and imaginative play in a place called Rainbow Valley, where they often gather and create their own world. Alongside the children’s experiences, the novel also explores the lives of their widowed father, the Reverend John Meredith, and his struggles raising his children alone. The children form strong bonds and learn lessons about kindness, responsibility, and understanding. The novel explores themes of childhood, friendship, family, innocence, and community life.