Possibly your cousin had a variety of scholarships that the researched, applied for and won, but she could also have been a Blue & Gold student.
Google UC and “blue and gold”. Essentially, the Blue & Gold program is a promise from the UC system that accepted students with a family income under 80k will receive enough in grant aid to cover tuition and fees. FAFSA is the name of the form that must be filled out each year to document income and demonstrate financial need.
Note that Blue & Gold only covers tuition and fees. Blue & Gold students are still responsible for things like room & board, books, transportation, etc.