Is a son entitled to demand money in exchange for not holding a wedding ceremony for him, similar to his brothers, and is a daughter given money in exchange for not holding a wedding ceremony for her in fulfillment of her wish?

The preponderant opinion is that justice among children in gifts and endowments is obligatory, unless there is a special need for one of the children that necessitates preferring them to the extent of their need. Whatever was spent on some children for their marriage, exceeding the need, must be given to the rest of the children similarly. As for what was commensurate with the need, equality is not required in it; rather, justice in spending is by giving each child according to their need. Ahmad stipulated that if he marries off some of his daughters and equips them, he should give all his children the like of what he gave her. Ibn al-Qayyim mentioned that whatever exceeds the expenditure is treated as a gift, while Ibn Uthaymeen said that if he marries off one of his sons, he is not obligated to give the others the same, but he should marry them off when they reach the age of marriage. If the son or daughter has agreed not to hold a wedding ceremony due to a specific circumstance, the father is not obligated to compensate them with the equivalent of the ceremony costs incurred for others, because this is considered part of the expenditure that is commensurate with the need.