The reason why a woman is not allowed to observe a naafil fast without her husband’s permission

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Check below answers in case you are looking for other related questions:
Her husband cannot produce children and he is addicted to haraam things
She is asking for separate accommodation; is that regarded as causing separation between her husband and his family?

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Related Answers:
Her husband is mentally ill and hurts her. How should she deal with him? Does he have any rights?
How should she deal with a husband who watches pornographic movies and does not give her her rights?
She wants to stay overnight with her family and her husband wants her to stay with his family
Her husband cannot produce children and he is addicted to haraam things
She is asking for separate accommodation; is that regarded as causing separation between her husband and his family?

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