Conversations with a 3-year old: We were getting into the van the other day and had the following conversation with Hayden:

Hayden: Look, I buckled my seatbelt all by myself!

Me: Wow, you're such a big boy!

Hayden: And I closed the door to the van all by myself too!

Me: I can't believe you can do that all by yourself!

Sean (to Hayden): Here are the keys, do you want to just go ahead and drive the van too?

Hayden (with a very serious tone): No, I'd better just stay here in my booster seat. The policeman would be very angry if I rode up front.

So the question is this, how old are they before they pick up on sarcasm?