Marion St. John Adcock Webb was an English writer of novels and poetry for children that presaged A. A. Milne, with her character "The Littlest One."
She was the daughter of the poet Arthur St. John Adcock and Marlon Louise Taylor, and sister of Almey St. John Adcock. She grew up at 42 Paddington Street and was admitted to St Marylebone School in Marylebone in January 1894, having just turned 5 years old.
Webb wrote poems for a series of fairy books illustrated by Margaret Tarrant, with whom she worked on around 20 books. The treatment of childhood by Tarrant and Webb is now regarded as sentimentalised, typical of its time. She had no children of her own.








