Michael-Castiel:
Well, genetically connected, then. I think there's something in their DNA that's drawn to madness, like a magnet. Probably a good thing you're there to balance it out.
It DID seem like a long shot until lately. Seems like the added time helped him a bit, even though he's been through one Hell of a lot. Or about fifty Hells of a lot. Are those a thing? They should be a thing.