Celebrate pet birthdays?

I have never celebrated any birthday for my pets. I do remember their birthdays for the purpose of remembering their exact ages. Then again, I only have aquarium pet fish at this moment and there are a lot of them. I won't be able to keep up with all the birthday celebrations if I treat them all fairly.

Usually people give birthday party to their pets only when they have a limited number of them. In most cases these pets are dogs and cats or other "higher life forms".

Maybe someday when I get a cat or a bird, I will give them a proper birthday party.