Gwen Mari born on the month of January has garnet as her birthstone while Stefani born on April has diamonds. One of the things that I wanted to give my daughters is a set of jewelry with their birthstones on it. It is easier (but more expensive) for me to give this to Ani since there are several jewelry shops that offer her stones. In fact, I already have several pieces which I got from mom that I am planning to give them in due time.