Is the son of the woman who breastfed a girl forbidden to the mother of the girl who nursed with him?

"The child does not prohibit the mother of his sister from fosterage if he was not suckled by her, because the prohibition relates to the suckled person and his descendants, not his collaterals or ancestors. The jurists have, however, exempted four types of women who are prohibited by lineage but not by fosterage: the mother of your brother or sister, the mother of your grandchild, the grandmother of your child, and the sister of your child."