Angel Is Getting Spayed!!!!!

[KittyGurl]

I have a question. How old does a cat have to be to get spayed?
I read in a book and on the internet that a cat shouldn't be older than one year old to get spayed. I was wondering if that was true.
Angel has been in heat a lot lately (about twice a month-usually lasts from 1 day to two weeks.) She is really annoying my grandma so she wants to get her spayed. Angel is four years old so I was wondering if it was okay to get her spayed.

Thanks everyone!