They don't have any protein!
In NZ we all shared a hotel room each night, so Caspian got used to sleeping close to us. Now that we're back he's had a hard time - his imagination is running strong, and so any little thing that wakes him up can trigger monsters (the bad kind, not like Cookie or Harry).
Su was comforting him after a waking-up incident, and saying things like "you have your Care Bears here to protect you," which apparently lead to a conversation about what Care Bears ate. Susan said, "They eat cloud sandwiches" which lead to the quote:
"But those are just made of air, they don't have any protein!"Susan then said she'd give him a magic "good witch of the North" kiss, to which Caspian responded:
"But that's too powerful!"He also said he "couldn't be Luke [Skywalker] brave, but I can be shot brave, like when I was little and didn't cry when I got a shot."
I also taught him a trick I learned (far too late, IMHO) of letting him keep a Star Wars blaster in his bed. He said "What if I accidentally blast Grover?" (Susan pointed out that good monsters were home in bed by now.)
He also proposed waiting while Su brushed her teeth and put on pyjamas. Su countered that she wanted to read, so Caspian offered, "Just read one of my 'That's not my...' books, they're short." - Su said she was reading Harry Potter, so Caspian said "Just read one page, okay?"