The stranger's child is Cecil Valance, who comes in 1913 as a visitor to Two Acres, home of the widowed Freda Sawle and her three children. The middle child, George, brings Cecil from Cambridge, where the two are members of the Apostles, an intellectual club-cum-debating society with a strong homosexual component to its membership. Cecil's family is from a higher social class -- his home Corley Court is quite grand in Victorian Gothic manner -- and he is a budding poet who, while at Two Acres, writes a poem in the autograph book of Daphne Sawle that becomes a "classic" of pre- WW1 England in something of the manner of Rupert Brooke's "If I should die . . ." (Brooke is mentioned, as is Lytton Strachey, as Apostles known, though not well, to Cecil and George). But Cecil is the stranger's child in another sense -- after his death in battle in 1916, and after his poems become better known, he becomes in effect the child of strangers, people in later generations who for aesthetic, economic, and sexual reasons are fascinated by his story. The final section of the book, set early in the 21st Century, shows him still an object of fascination. He is, however, never pinned down; he remains a mystery to the end. In the opening section -- the only one in which he is alive -- we are given no access to his inner life. All we know of him we have to infer from the reactions of the Sawle household. "The stranger's child" is also a phrase from Tennyson's "In Memoriam" (T. had also been an "Apostle"), and the section of the poem in which it appears is read by Cecil in the first section of the book. It's no accident that it is by far more powerful and moving than anything that Cecil manages in the way of poetry, and it foreshadows the fate of Two Acres and of Cecil himself.