In the second book, "Harry Potter and the Chamber of Secrets", Rowling pits Harry against Tom Marvolo Riddle, a memory of Lord Voldemort locked up in a secret diary that Ron's younger sister Ginny Weasley finds in a bathroom. When Muggle (non-magic) parentage students are found being petrified, many think that Harry may be the one behind the attacks, making him become more detached from his classmates. At the height of the book, Ginny Weasley is found to be missing. To rescue her, Harry battles Riddle and the monster he controls that is hidden in the Chamber of Secrets.