After Scout escorts Boo back to his home, she pauses on the Radley porch and, remembering her father's advice about how "you never really know a man until you stand in his shoes and walk around in them," she looks out across her neighborhood. Standing on Boo's porch in Boo's shoes, Scout now sees her little world from Boo's eyes, as if it is he standing there (or peering through the window), watching the events of the past two years. She understands that Boo has probably seen much of the children's activities, and standing there she remembers them more vividly than ever before: running to meet Atticus, acting out the Radley Game, fighting on the sidewalk, finding gifts in the secret knothole, and watching Atticus kill the mad dog. But it is Boo seeing them now:
Summer, and he watched his children's heart break. Autumn again, and Boo's children needed him. (Chapter 31)
Scout "sees" that Boo has been watching over Jem and Scout all along--keeping his eye on them even when they do not see him--and that they have become his children, too. She understands now that Boo must have lived up to his reputation as a nocturnal prowler, but probably only for the good deed of being their protector against the evils that exist, even in their little world.