When Neville Longbottom, the boy who kept losing his toad, was called, he fell over on his way to the stool. The hat took a long time to decide with Neville. When it finally shouted, "GRYFFINDOR," Neville ran off still wearing it, and had to jog back amid gales of laughter to give it to "MacDougal, Morag."

Harry Potter and the Philosopher's Stone - Chapter 7 : The Sorting Hat
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