"James Potter and Sirius Black. Apprehended using an illegal hex upon Bertram Aubrey. Aubreys head twice normal size. Double detention."
-- one of Filch's cards (HBP24)
"It must be such a comforting thing that, though they are gone, a record of their great achievements remains."
-- Snape commenting on the story of Bertram Aubrey (HBP24)
Hogwarts student, 1970s
James Potter and Sirius Black once received detention for hexing Aubrey and causing his head to grow twice its normal size (HBP24). Harry learned about it when Snape gave him a detention and made him copy-over Mr. Filch’s filing cabinet cards.