Author Harper Lee brings up the novel, The Gray Ghost, once again in the final pages of TKAM. The Gray Ghost is the same book that Jem had won on a bet from Dill much earlier in the story, and it is the first book that Atticus happens to see in Jem's room while he watches over his son following the attack by Bob Ewell. Atticus was already halfway through reading the book to himself--"One of the few things I haven't read," he said pointedly--but he quickly turned back to the beginning and began reading aloud to Scout, who he knew needed a good night's sleep after the events of the long evening.
... I was puzzled by his amiable acquiescence. He was shrewder than I, however: the moment I sat down I began to feel sleepy.
Lee ties in a symbolic connection between one of the book's characters, Stoner's Boy, and Boo Radley. Stoner's Boy, like Boo, had been accused of acts for which he was innocent; and, like Boo, he also turned out to be good, not evil--a fact which the sleepy Scout recognizes.
"... they didn't know what he looked like, an' Atticus, when they finally saw him, why he hadn't done any of those things... Atticus, he was real nice..."
"Most people are, Scout, when you finally see them."
The fine rain that falls outside serves to wash away the last vestiges of Scout's youthful innocence, altering her outlook of the neighborhood and giving her a new and more mature view of the little world around her. The rain made "the street lights look fuzzy," and she suddenly "felt very old" as the mist served to intermix her remembrances of the events of the past two years with the new light in which she now saw the things around her.