Follows Instructions Well

Apparently, Charlie inherited the literal gene and/or follows directions well ...

Charlie to Grandpa: "Let's have cookies for a snack."
Grandpa to Charlie: "Good idea. Ask Grandma if she'd like a cookie."
Charlie to Grandma: "Grandma, would you like a cookie for a snack?"
Grandma to Charlie: "I don't want my own cookie but I'd like a bite of Grandpa's."
Charlie relays Grandma's request to Grandpa.
Grandpa to Charlie: "OK. Here's a cookie. Tell Grandma she can have one bite, but then she has to give it right back to me."
Charlie brings cookie to Grandma and tells her what Grandpa said. Grandma takes bite of cookie and asks Charlie to give it back to Grandpa. Charlie refuses.
Charlie to Grandma: "No Grandma. Grandpa said you could have one bite and then you have to bring it back to him.
Grandma to Charlie: "I think it would be ok if you brought the cookie back to Grandpa."
Charlie says no.
Grandma to Grandpa: "Grandpa, will you please tell Charlie it's ok for him to bring you the cookie?"