Does the husband have the right to demand the costs of the wedding, the dower (Mahr), and gifts when the wife requests Khulʿ, and is the age of حضانة (custody) determined based on the madhhabs (schools of thought) or the judge's discretion?

Al-Khul' (divorce at the instance of the wife) is permissible between spouses if there is fear that they may not be able to uphold the limits set by Allah, and it takes place for an amount agreed upon. The mother's custody extends to both male and female children as long as she does not remarry. The jurists have differed in their opinions regarding the age limit for custody after separation.