What should she do with her husband who is committing adultery and his mistress is pregnant?

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Check below answers in case you are looking for other related questions:
If she accuses her husband of zina, does she have the right to separate from him by means of li’aan?
Ruling on one who committed zina with a non-Muslim woman when he was not married

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Related Answers:
Responsibility Towards the Child of Fornication
If a child is the illegitimate offspring of two kaafirs, can he be named after the zaani?
Ruling on illegitimate children
If she accuses her husband of zina, does she have the right to separate from him by means of li’aan?
Ruling on one who committed zina with a non-Muslim woman when he was not married

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