Rinoa's mother

[Shattered Dreamer]

The in-game Tutorial practically states that Julia is Rinoa's mother.

Eyes On Me
Julia Heartilly's song. Julia married the Galbadian General Caraway after releasing "Eyes On Me". Gave birth to a girl one year later. Julia died in a car crash at age 28, right before her daughter turned 5.

I suppose that kinda answers the thread:P I'l have to give that tutorial section a read at some point