NightlyPoe said:
I'd like to say that his death might be a hopeful thing, but that sister of his seems like the real hard-liner of the family, and less likely to politely drop dead.

It might not be as clear-cut as that. Apparently, he was confident enough in his living a long and fruitful life that he never actually bothered to designate an official successor should anything happen to him. North Korea is technically still a republic rather than a monarchy, it's just been ruled by the same family for 70+ years because Kim Il-Sung and Kim Jong-Il were actually smart enough to have their line of succession sorted out.