Peter Pan and Wendy by J. M. Barrie

From chapters.ca:
Peter Pan, the boy who refused to grow up, is one of the immortals of children's literature. J. M. Barrie first created Peter Pan as a baby, living in secret with the birds and fairies in the middle of London, but as the children for whom he invented the stories grew older, so too did Peter, reappearing in Neverland, where he was aided in his epic battles with Red Indians and pirates by the motherly and resourceful Wendy Darling.

There are a number of prequels and sequels written by various people, but I will let you research those for yourselves.