Mary Phillips
From Tardis Wiki, the free Doctor Who reference
Mary Phillips was a fellow student of Sally Sparrow. She made up a song about Sally's frizzy hair. Sally punched Mary and was punished for it. When trying to prove how he was somehow in a conversation with Sally from twenty years in the past, knowing what was being said, the Ninth Doctor repeated this story to her. (PROSE: What I Did on My Christmas Holidays by Sally Sparrow)