Missing keys

9/13/11.  My car keys were totally missing this morning.  I could not find them anywhere.  So I called Nick (my nephew) and asked him to look for the keys for me.  He found them right away.  They were right up against the front door in the living room.  Now there is no way they could have been there when I left.  The door opens up into the living room.  I would have noticed the keys when I tried to open the door.
Nick's key didn't work on the front door, even though the locks are the same for front and back doors.  So that is why he went in through the back door.