If someone wants his brother’s wife to become maḥram to him, some [jurists (fuqahāʾ)] have said that he must contract a temporary marriage (mutʿah) with a breastfeeding girl for two days, for example, and in those two days – while fulfilling the conditions that were mentioned in Ruling 2492 – his brother’s wife must breastfeed the girl so that she becomes the nursing mother of his wife.
However, if the brother’s wife breastfeeds the girl with the milk that is related to the brother, this rule (ḥukm) is problematic (maḥall al‑ishkāl) [i.e. based on obligatory precaution, the rule is not established in this case].[1]