chinese grapes anyone?

I was driving the Monkeys to church tonight and Noah decided to tell me a joke he made up.

Noah: What is the longest wall in the world that has grapes on it?

Me: I don't know. What is it?

Noah: The GRAPE wall of China!

I laughed the obligatory laugh, even though the whole Great Wall covered in grapes really did make me laugh.  A couple of minutes passed and I heard this exclamation from the backseat:

Jacob: I ACTUALLY GET IT!