A.A. Milne grew up in a school - his parents ran Henley House in Kilburn, for young boys - but never intended to be a children's writer. Pooh he saw as a pleasant sideline to his main career as a playwright and regular scribe for the satirical literary magazine, Punch.
Writing was very much the dominant feature of A.A. (Alan Alexander)'s life. He joined the staff of Punch in 1906, and became Assistant Editor. In the course of two decades he fought in the First World War, wrote some 18 plays and three novels, and fathered a son, Christopher Robin Milne, in 1920 (although he described the baby as being more his wife's work than his own!).
Observations of little Christopher led Milne to produce a book of children's poetry, When We Were Very Young, in 1924, and in 1926 the seminal Winnie-the-Pooh. More poems followed in Now We Are Six (1927) and Pooh returned in The House at Pooh Corner (1928). After that, in spite of enthusiastic demand, Milne declined to write any more children's stories as he felt that, with his son growing up, they would now only be copies based on a memory.
In one way, Christopher Robin turned out to be more famous than his father, though he became uncomfortable with his fame as he got older, preferring to avoid the literary limelight and run a bookshop in Dartmouth. Nevertheless, he published three volumes of his reminiscences before his death in 1996.