Luna Lovegood's Patronus is a hare, and is first seen in Harry Potter and the Order of the Phoenix during the scene that Harry is teaching the members of Dumbledore's Army the Expecto Patronum charm.

We know that Harry's Patronus is a stag like his father and ... of Dumbledore's Army with in Harry Potter and the Order of the Phoenix. Our thanks to the nature-lovers who spotted this lost ...