I got a card from my 15 year old grandson that is very personal between him and me. He made it on his computer. The boy and I share a similar sense of humor. It was a quote by Albert Einstein on the front with a joke he wrote inside only he and I would think was funny.
I started this "I'm a genius" BS with him because he really is one. His IQ is in that range. Yet he is a very likable young man with an absolutely great personality. He's self motivated to do the best he can at anything he undertakes. He hates taking second place in anything, he has a wall full of trophies to prove it. He's the kid I never had. I love him deeply.