is ginny older than harry?
Ginny specifies that she is 3 years older than Harry was when Harry faced Voldemort at the end of his first-year. So when Harry faced Voldemort in 1992, he was 11 years old. The battle at Department of Mysteries happens in 1996, when Ginny was 14 years old. So she is three years older than how old Harry was back then.