” Grandma, are the Muppets real?”
“They are puppets, Ty. So they have people who carry them around.”
“But I’ve seen their feet.”
“Then they are really fancy puppets!”
“And I have seen their backs,too.” (no smiles.)
“I have no idea how they do that, Ty, but Uncle Rob knows everything about them. And – he even knows the guys who carry them around.”
“He does? Well, I would like their names.”
I think he would like to report them to someone.
tricialottwilliford 
A really good documentary that they might actually like is called “Being Elmo”. It talks about the puppeteer behind Elmo and shows a lot of the behind the scenes stuff.
I loved that! It’s on Netflix! I’m wondering if it might ruin it for him though…but maybe not if he’s asking questions like that… :)