It became a perennial best seller, spawning several sequels, and was animated by Disney as part of the feature anthology Melody Time. During World War II, he worked in Hollywood producing training films for the United States Army Air Forces.
It regularly made it to the top of the bestseller charts, leading to several sequels, which were animated by Disney as part of the feature anthology Melody Time. During World War II, he produced training materials for the United States Army Air Forces while working in Hollywood.