A Tumblr post published in 2014 and just shared by Bustle contains a fan theory that'll totally change how you think about Harry Potter's family: Aunt Petunia was a witch.
The creator of the theory, known as sulietsexual on Tumblr, proposes that Petunia used her magical abilities throughout the series and was actually the one responsible for breaking Aunt Marge's glass.
It might seem random at first, but it won't once you read this J.K. Rowling quote from 2004: "You might have got the impression that there is a little bit more to Aunt Petunia than meets the eye, and you will find out what it is. She is not a squib, although that is a very good guess."
But then, she stopped herself: "Oh, I am giving a lot away here. I am being shockingly indiscreet."
Plus, Bustle points out, Petunia appears to withhold a confession in Harry Potter and the Deathly Hallows.
"She stopped and looked back," it reads. "For a moment Harry had the strangest feeling that she wanted to say something to him. She gave him an odd, tremulous look and seemed to teeter on the edge of speech, but then, with a little jerk of her head, she bustled out of the room after her husband and son."
Now, it makes a lot of sense that Petunia was upset about not getting into Hogwarts and asked Professor Dumbledore if it was a mistake. Maybe her contempt for the Potters came not from a distaste for magic, but from resentment that they were more magical than her — or perhaps even from self-loathing.
Unlike some fan theories, this one might actually check out.