Is the wife obligated to return the dower and gifts after leaving her husband and claiming divorce, knowing that the husband did not divorce her Islamically, and she has married another and had children with him?

If a man divorces his wife without stipulating a compensation, the wife is entitled to the full mahr (dowry), and she is not obliged to waive any part of it. As for gifts, they may be reclaimed if the divorce was caused by them. If the divorce or khul' (divorce at the wife's instance) occurs with compensation, then what they agree upon is binding. The divorce with compensation should not harm the woman, but if she dislikes remaining with her husband, he may stipulate compensation.

A married woman is not permitted to marry another man until after her divorce and the completion of her iddah (waiting period). Her marriage before that is null and considered zina (fornication/adultery), and she must separate from the second man and return to her first husband. The wife does not have the right to stipulate returning to her husband in exchange for him writing properties in her name; rather, she must return and obey, and it is forbidden for her to leave his house without his permission. The wise should intervene to advise the woman and prevent her from the void marriage.