Ginny Weasley. Ron's only sister, the youngest of the Weasley children

Ginny is the youngest of the Weasley children and the only girl. One year younger than Ron, Harry and Hermione, Ginny Weasley starts school at Hogwarts in the beginning of Harry Potter and the Chamber of Secrets. Harry and Ron watched her sorting ceremony through the window of the Great Hall after crashing Arthur Weasley's flying car into the Whomping Willow. Even before she reached Hogwarts Ginny was a central character in the events of Harry's second year, having had Tom Riddle's diary slipped in amongst her books by Lucius Malfoy. As she wrote her troubles into the enchanted diary the memory of Tom Marvolo Riddle, or Lord Voldemort as he is now known, drained her life into itself and used her to open the Chamber of Secrets. After she was lured down into the Chamber itself so that Riddle could finish leeching her life into himself, Harry and Ron forced Professor Lockhart into going to the rescue, rather than running away as he had intended. During the rescue Ron and Lockheart got separated from Harry who went on to save Ginny alone.

Since before Ginny started school she had a crush on Harry, and used to be almost incapable of speech in his presence. Three years at school seems to have weakened his effect on her somewhat and during her fourth year she went out with Michael Corner from Ravenclaw and lately Harry and Ron's friend Dean Thomas.