"Daddy, why can't zombies move fast?"
Hmm, Dr. Spock doesn't cover questions about the undead from five year-olds. Does Dr. Van Helsing have a parenting book? Maybe there's a need for this kind of thing, maybe I should write "What to Expect When You're Raising a Vampire Hunter."
The question is really my fault, anyway. We were playing a game on the way home from school where I pretend I don't know where he is, even though he's riding on my shoulders. And while he's up there (this started around Halloween), he makes spooky noises to scare me, like ghostly moaning, witches' cackles, jingling skeleton bones, etc. And then he makes a noise and says it's zombies. "Well," I say, "I don't have to worry too much because zombies move pretty slow."
Hence, later, the question. My answer touches on logical reasons, you know, the crumbling bones and wasting muscles, etc.
And also, "Hey bud, you know there's no such thing as zombies, right?"
Later, he asks his mother the same question, just to check up on me, I guess.