The Influence of the Woman Whose Milk a Child Is Given Also Passes On
Question
If one woman nurses another woman’s child, will some portion of that woman’s habits pass into the child, whether the habits are good or bad? And will nikah between the woman who nursed and the one who was nursed be permissible or not? Or is the relationship between the two that of brother and sister?
Answer
By nursing within the period of suckling, that child becomes the milk son of that woman and that woman becomes the milk mother of that child, and all the children of that woman, however many there are, become the brothers and sisters of that child; nikah with them becomes haram.
Source: Fatawa Mahmudiyya
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