I was just outside and there’s a party going on. The DJ put on Happy Birthday in Spanish and it went:
Cupleaños feliz
Cupleaños feliz
Cupleaños feli-iz
Cupleaños feliz

Que embotado!

The version I learned from Senor Celaya was mucho divertido:
De las vuelas las luces
Ellas quiren decir
Que tus tengas [su nombre]
Cupleaños feliz

Isn’t that much more festive? And less, uh…repetitive?