Is it permissible for me to demand custody of my two daughters in exchange for divorce and the full return of the dowry, due to the ill manners of the wife's mother and her influence on the upbringing of the girls?

The majority of scholars are of the opinion that custody is not forfeited by the mother even if she initiates Khul' (dissolution of marriage at the wife's instance), provided that her right to custody is not waived. The general rule, when a couple separates, is that custody belongs to the mother, unless there is a valid impediment to custody. Issues of custody are referred to the Sharia judge for resolution.

The questioner is advised to strive to reconcile with his wife and clarify that her obedience to her husband is more incumbent than her obedience to her mother, and that it is not permissible for her to refuse to return to her home out of obedience to her mother. If the mother is corrupting the wife, the husband has the right to prevent her from visiting the wife. Divorce is the last resort if reconciliation efforts fail.