When it's your real-life birthday in Animal Crossing: New Horizons, the anthropomorphic animal villagers get very excited.
Isabelle kicks things off by wishing you a very public happy birthday in the morning announcements. Then your "Best Friend" will come to find you.
What ensues is a surprisingly in-depth birthday party with the three villagers you're closest to. For me that's Sheldon, Raymond, and Stella. Sheldon was one of my two original villagers, and he hosted the party.
It includes some gifts! (Sheldon gave me the Birthday Sunglasses.)
Cupcakes ... in a piñata? WTF?
But the fun doesn't stop there. If you go to the town center, there'll be an extra-special surprise waiting for you there.
K.K. Slider will aggressively flirt with you and then serenade you in his black music void while more happy birthday messages drift on by.
It's all ultimately pretty simple, but it's a great example of what New Horizons does best: entertain and distract us with simple pleasures and quirky characters in a colorful world where only good things can happen.