August 24, 2016 10:54 AM EDT

After a series of Harry Potter sketches created by J.K. Rowling herself went viral Tuesday after being discovered on Pottermore, fans began to notice a surprising detail about one of the drawings. In an illustration featuring the Gryffindor gang during “The Midnight Duel” chapter of The Philosopher’s Stone, there is a fifth character named Gary sneaking around Hogwarts with Harry, Ron, Hermione and Neville.

But that’s not all. Rowling later revealed on Twitter that Gary was the original Dean Thomas. “Dean Thomas was called Gary in the first draft of Philosopher’s Stone,” she wrote. “I renamed him after a boy I knew!”

She also added that she had completely forgotten about this change until she saw the image again.

Write to Megan McCluskey at

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