User blog comment:KingOfSpriters12/One Direction: This Is Us (specifically what I think of it)/@comment-26124383-20130831214639/@comment-26124383-20130901023258

Regeneration. He is a Time Lord that is nearly immortal but if he's ever dying he can regenerate. It would change his appearance and personality but he'd be in the core, the same person. He's had 12 regenerations so far, the 12th coming in Season 8 of the Revived Series next year.