Telling my father that he qualifies for "grandfather discounts" instead of saying senior discounts...It was priceless...even more so when he A) smiled at the joke, and B) I heard him repeat it to himself and chuckle when I left the room...
Note: He doesn't laugh at anything! It always makes my day if I can make him crack a smile...
Oh, just realized something...I said grandfather to indicate that he is really, really, old...older than a senior...not that he will be a grandfather anytime soon...just to clarify... :-)