Do your sims ever die unexpectedly?

I've never purposefully kill my sims, but accidents do happen sometimes, like a kitchen fire or accidental drowning in the sea, and townies sometimes freeze to death. I understand when there is a blizzard, but most recently Nina Caliente froze to death in Oasis Springs while going on the water slide and it wasn't even snowing outside. In retrospect I think maybe she was bugged because she was on that waterslide the entire day.