Is it permissible to marry the daughter of the sister of a foster sister?

Your being a brother to a woman through suckling has two scenarios: Either you suckle from your mother, or both of you suckle from a foreign woman. In these two scenarios, she alone is your sister, and the rest of her sisters are not mahram to you. It is permissible for you to marry her sister or her sister's daughter. The other scenario is that you suckle from her mother. In this case, you become a brother to all her siblings, both male and female, and her sister's daughter becomes forbidden to you because you are her maternal uncle through suckling.