Remus John Lupin was an only son of Lyall and Hope Lupin (née Howell). At the age of 4, he was bitten by the foul werewolf Fenrir Greyback when his father-Lyall Lupin- insulted all werewolves. Fenrir tried to kill him but Remus got saved by his father. However he became a fully fledged werewolf. His parents were both upset by this, because it meant he could not go to Hogwarts School of Witchcraft and Wizardry. However, when Albus Dumbledore became headmaster, he let Lupin go to Hogwarts. He had a tunnel built so that Lupin could sneak out of the school during the times when he became a werewolf. This tunnel had the Whomping Willow (a violent tree that attacks those who get near it) built over it, so nobody could get to him by mistake. The tunnel led to the Shrieking Shack, a building in the wizarding village of Hogsmeade, said to be the most haunted of them all. When Lupin was in the Shrieking Shack as a werewolf, he had no humans to bite, so he often bit himself. These bites led to cries of pain that led the villagers to believe that the building was haunted.