harry was born by a wizard ( james potter) and a mudblood (lilly potter) ( mudblood means her parents wernt wizards) voldemort stormed into there house on the 31st of October when harry was one and he killed james on the stairs or landing I think and went to kill harry but lily cast herself in between the spell killing herself but because she done it out of love the spell rebounded also killing or supposedly killing vodemort then voldemort latched on to the only other living thing in the room at that time creating harry the seventh horcruxe that he didn't mean to make in harry shown in the deathly hallows part 2