Clay Tablet

Me: You need help getting out of the car, buddy?
Son: No dad, I’m good.
(after getting out and struggling to put on his backpack)
Son: Man, this is heavy. It’s like I’m carrying clay tablets or something.
Me: Ha ha. Who are you Moses? Did he have a backpack?
Son: No, he had a donkey.
Me: We could bring your brother.