Imagination

Andy is a force of something.
The child will talk your ear off.
He also will manage to get his brother and sister upset because he is pretty forceful about imposing his view of how things are going imaginatively.
Case in point: We're driving. Andy is playing (with sound effects) Star Wars.
Doug is playing along (nothing like hearing "Stay on target...Stay on target" coming from the back seat).
Andy decides that Doug did the wrong thing (I think Doug was Anakin) and is now bad and Andy claims to have shot down Doug's ship.
Despite parents claiming that they are pretending and that Doug can pretend something different if he doesn't like what Andy says...we end up listening to wailing for five minutes because Doug is upset that Andy has shot down his ship and that Andy will not change that he has shot down Doug's ship.