I forgot haha.
So now that I remember it, it was actually not Zanki but the cadaver deck my school provides for anatomy. My 4 year old asked if I'd lie with her sister and her for a little bit while they fell asleep. It was close to an exam, so I figured I'd knock out some cards while they were falling asleep, and they weren't looking so I did anatomy.
Well one of them happened to look over and ask me what I was looking at. So I told them (they are very curious about what I learn at med school) that I was looking at pictures of dead people so I could learn anatomy. They asked what happened to them, and I said they volunteered to be used to teach us after they died so that we could learn to take care of people.
One of them asked me why she died (the cadaver), and I said I think she was just old. And she said, how does that happen? And I didn't even think about it and said, everyone gets old.
And she opened her eyes really big and said, you mean I'm going to get old and DIE!?
That was followed by much wailing and gnashing of teeth, and my wife banning me from putting them to bed.