Keith's Reason

  Robert laughs.    He always finds it interesting that people think they can scare him with a gun.  First of all, unless Keith doesn't have to move a single muscle to fire a gun, Robert is confident he can detect Keith's trigger pulling before Keith even pulls the trigger.  This usually means Robert can avoid being shot at.   

Even if Robert is shot, he will appear to be shot, but he will not die anyway.

Even if Robert will die, he is not the kind of person who will give the game away just because someone threatens him. 

"Good lord, Keith! You can shoot me all you want.  I will not take you anywhere unless you tell me what you want from my Grand Uncle Robert, OK?"

Keith grunts, teeth grinding.  He is trying very hard to restrain himself from shooting Robert.