As an infant, his mother died in a carriage accident. That same accident indirectly brought Dio Brando into his life, because Dario, Dio's father, unwittingly saved Jonathan's father while he was preparing to steal from the wrecked carriage. Twelve years later, Dario apparently died of illness and Dio went to live amongst the Joestars. Dio, despite Jonathan trying to be friends with him, would become his nemesis both as a childhood rival and as an undead enemy. At the young age of 12, when Dio came into his life, he meets and falls in love with Erina Pendleton, but Dio shatters this relationship for a considerable time through his evil ways, by kissing Erina and boasting about it.