"I didn't think I was going to be able to go and then two days before I decided to go and I had to find a dress and get ready at the last minute, but it was really fun. The theme was enchanted garden," Fanning said on Monday's edition of "The Tonight Show with Jay Leno."
Fanning, 16, has starred in the films "I Am Sam," "The Cat in the Hat," "Man on Fire," "War of the Worlds" and "The Runaways," as well as the "New Moon" and "Eclipse" installments of the "Twilight" franchise.
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