A fake diagnosis that you tell your friends your Dad just got. They will feel bad for a split second, but if they are smart they will catch on.
Person 1: "You look sad, why are you sad?"
Person 2: "Well you see, my Dad just got diagnosed with O.L.D."
Person 1:"O.L.D.? Oh im so sorry, I hope he gets better."
Person 1:"Wait, whats O.L.D.?"
Person 2:"Hes old, that's all."