Who is Sandra Dobbs from Crazy Lady! and what is their importance?

Sandra is Vernon's younger sister, and one of the novel's minor characters. Over the course of the novel, Sandra steals a book from Vernon that he was given by Miss Annie. At first, Vernon is angry at her and demands she give him back the book. Later, he reflects on the fact that Sandra never had anyone to read to her.... as their mother died when she was too young to remember. Vernon, however, has those memories and allows her to keep the book, which she then reads to Ben.