Happy Chaos!
You have to play this game. You just have to. Kids barely old enough to read can play alongside grandparents (as long as everyone has some degree of mobility). There will be yelling. There will be gesturing. There will be high-fives. Everything will be happening at once and everyone will be grinning so much their face hurts. Your abs will mysteriously hurt a day later, and then you'll realize it was from all of the laughing. This game only ends when no one can manage to wheeze out, "One more round?"