What are the prohibitions established through fosterage (Rada'ah)?

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Two categories are explicitly mentioned as prohibited through fosterage: nursing mothers and their mothers and grandmothers ascending through the chain, based on the verse, "and your mothers who have suckled you, and your foster-sisters" (Quran 4:23). Furthermore, any woman who breastfed you, or whose mother breastfed you, or if you both drank from the same woman's milk, or if you and she drank from the milk of the same man (even if from different wives), makes her your foster-sister and forbidden, based on "and your foster-sisters" (Quran 4:23).