I am slightly, shall we say, competitive, when playing games. I have had to tone this natural inclination down since having a child, and have done my best to model good sportsmanship. He makes it easier, because he doesn't gloat (usually) when he wins, and congratulates the winner (usually) if he doesn't.
But I didn't have to tone anything down recently when Grandma bought the game of Yahtzee and we played it with him for the first time. We explained the rules, and how hard it is to role an actual Yahtzee, and what does he do, the very first roll? Ever in his life?
He rolled a Yahtzee, that's what! We all screamed, and he laughed so hard, looking from face to face, and I think he knew how incredibly rare and exciting it was. He beat the pants off of us, rolling another Yahtzee later in the game. And tonight, his first night home, was a repeat of that first game. He rolled all ones the first shake, and managed to get another later in the game.
I don't even mind not winning when I get to see his face after Yahtzee.