1. They both blow out candles on July 31 (happy birthday, JKR!). And that’s not the only influence Rowling had on her characters: She’s said that Hermione is a bit like her when she was younger, and her favorite animal is an otter—which is, of course, Hermione’s Patronus. Plus, both Dumbledore and Rowling like sherbet lemons (Rowling said that the wizard’s “got good taste”).
2. Harry doesn’t cast a single spell for the duration of the first movie.
He performs wandless magic, like when he vanishes the glass at the zoo, and some kind of magic-y things happen when he’s holding a wand, like at Ollivander’s, but he never actually successfully casts a spell by saying the incantation out loud.
3. In 2000, Scholastic gave schoolchildren across the U.S. the opportunity to ask Rowling questions about Harry Potter. When one student asked her, “What made you think of the people’s names and dormitories at Hogwarts?” Rowling responded, “I invented the names of the Houses on the back of an airplane sick bag! This is true. I love inventing names, but I also collect unusual names, so that I can look through my notebook and choose one that suits a new character.”
4. The actor who plays young Voldemort in Half-Blood Prince – Hero Fiennes-Tiffin – is the nephew of Ralph Fiennes, who plays the older Voldemort.
But it wasn’t his family connections that got him the part, according to director David Yates.”It was an advantage that he looked very similar to Ralph … but primarily I went for Hero because of this wonderful haunted quality that seemed to bring Tom Riddle alive on-screen for us,” Yates told USA Today in 2008.
5. Rowling’s mother, who had multiple sclerosis, died in 1990, after which Rowling suffered a period of depression. She would use the experience to characterize the Harry Potter’s dementors, creepy creatures that feed on human emotion. “It’s so difficult to describe [depression] to someone who’s never been there because it’s not sadness,” Rowling told Oprah Winfrey. “I know sadness. Sadness is to cry and to feel. But it’s that cold absence of feeling—that really hollowed-out feeling. That’s what Dementors are.”