the boy and the advent calendar

So Grammie and Papa gave Ashleigh & Ryan advent calendars at Thanksgiving.   Well, the 5 year old girl understands.  Each day until Christmas you open up a little door revealing a picture and a small piece of chocolate.  The nearly 3 year old boy does not understand.  You just don't open each little door at once and eat all the chocolate right now?  Huh?  Patience?  Bah, patience!  It was a serious challenge to get the boy to comprehend it all... we're on day 4 and only one extra door has been opened... not too bad.