They committed zina, then they repented and got married, but she is sure that they will be punished and their children will be deformed

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Check below answers in case you are looking for other related questions:
Repenting From Adultery
Abrogation of the verse ordering the confinement of an adulteress in a house

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Related Answers:
He committed zina with a woman; is he allowed to marry her daughter?
Is there any expiation for having intercourse with a woman in her back passage?
She repented from a haram relationship in which she lost her virginity. Should she marry who fornicated with her?
Repenting From Adultery
Abrogation of the verse ordering the confinement of an adulteress in a house

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