The Davies boys (the family only used the double surname Llewelyn Davies in formal contexts) were the sons of Arthur and Sylvia Llewelyn Davies this family were the inspiration for Peter Pan and were adopted by J. Barrie after the death of their mother.
The boy castaways of Black Lake Island, being a record of the terrible adventures of the brothers Davies in the Summer of faithfully set forth by Peter Llewelyn Davies - @ Beinecke Rare Book & Manuscript Library, Yale
Playing with an ax. George Llewellyn-Davies, Jack Llewellyn-Davies and Peter Llewellyn-Davies. Picture taken by J. Barrie, as published on the “The Boy Castaways” book by Barrie himself, under Peter’s name.