Ali loved Cari so much! And they can totally bond over being little sisters. When was she in Cali? Ali was there from '09-'13. If it works out that they were in Cali at the same time, we could make them be friends over the little sister thing first and then when they came back and maybe met through Cari, it was all, "hey! I know you!"
EDIT: She would totally call Brielle and herself, "the little sistas from other mistas."