The clue

Apparently I gave you a clue about the existence of Santa last year. I told you that we could take something back to Target if you didn't like it. You said this clue led to a question that led to a big conclusion. 

Tonight, we discussed and I had some arguments about how that wasn't a clue that you found acceptable. Nevertheless, the jig may be up after 10 years. I just hope you don't spoil it for your brothers. 

Specifics

Conversation with daddy about how lungs get oxygen. He decides to compare them to food on a table. 

Chrys: "You breathe in oxygen and other stuff."

RC: "and your lungs sort it out and put the other stuff back?"

Chrys: "No. Imagine you put 50 hot dogs and 20 cookies on the table. You don't want any hot dogs. How many hot dogs do you have to pick up?"

RC: "50 because you didn't eat any."

Me: "No no no. Not at the end. While you're eating. How many hot dogs do you have to move or pick up to get your cookies."

RC: "Oohhhhhhhhh. Zero"

Literal. For $1000 please.