Harry Potter & The Sorcerers Stone question?

Sirius is Harry's godfather; also his father's best friend. Not actually related though. He couldn't raise Harry after his parents were killed because he was framed for their murder and was in Azkaban prison. Everyone thought he was working for Voldemort and was a crazed killer who had betrayed Harry's parents and killed them. Harry got sent to live with the Dursleys because they were his closest living relatives, and also to keep him safe and get him away from Voldemort, who was trying to kill him.