Is Nikah with a Milk Sister Valid?

Question

Rahim and Karim are two brothers. Karim has a milk sister (a sister who shared the same milk). People wish to marry this sister to Rahim — will this be valid? It is written in Bihishti Zewar (“Heavenly Ornaments”) that Qadir and Zakir are two brothers; Zakir has a milk sister, and her nikah can take place with Qadir but cannot take place with Zakir.

Answer

With all the children of the woman (Karim’s mother) whose milk this girl drank, prohibition by suckling is established with respect to this girl. Her marriage will not be valid with either Karim or Rahim. The gist of the mas’ala in Bihishti Zewar is that if one brother drank the milk of some unrelated woman, prohibition by suckling is established for him, but it is not…

Source: Fatawa Mahmudiyya

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