What is the punishment for a wife engaging in kissing and hugging with her husband's brother, and what should be done if the relationship between them develops?

The woman's action is forbidden (haram), and she must repent immediately. The imprisoned brother must verify and not rush to accuse his brother, because the wife's accusation is not sufficient. The imprisoned man's brother must repent to Allah if what the wife said is true, as he should have respected the sanctity of his brother. The imprisoned brother is advised to be patient and to remind his wife and his brother of Allah. If it is confirmed that they committed immorality, then concealment (al-satr) is better. The execution of legal penalties (hudud) is for the Muslim ruler or his representative, not for individuals.