Can I marry the daughter of the wife of my father whom she had from another man? She is not my sister. And his wife is not my mother.
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
It is permissible for you to marry this girl as long as there is no suckling relationship between you and her. This is because there are no marriage impediments in this case, which are: family lineage, relationship by marriage, and suckling.
Allah knows best.
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