Really Rosie is a musical with a book and lyrics by Maurice Sendak and music by Carole King. The musical is based on Sendak's books "Chicken Soup with Rice", "Pierre", "One was Johnny", "Aligators All Around" (Which comprise the 1962 book "The Nutshell Library"), and "The Sign on Rosie's Door". Sendak based the story on a demonstrative little girl who used to sing and dance on the stoop of her building, whom he observed while he was a little boy growing up in Brooklyn.