The Tale of Peter Rabbit, was originally created in 1893 as a letter to Noel Moore,the five year old son of Potter's former governess, Annie Moore. The boy was ill, and Potter wrote him a story letter with pictures to help him pass the time and to cheer him up. The letter included sketches illustrating the narrative. The book was published in 1902.
It was always a favorite of mine. I loved the illustrations.