Is it permissible, in Islamic law, to demand support for a 16-year-old son who is studying in secondary school, after his father stopped providing the agreed-upon amount for his needs?

A man must spend on his poor and needy parents and children if he has the means to do so. This obligation is rooted in the Quran, Sunnah, and scholarly consensus. Allah Almighty says: (And upon the father is their provision and their clothing according to what is reasonable). And the Prophet, peace be upon him, said to Hind: (Take what suffices you and your child, according to what is reasonable).

Three conditions are required for this expenditure to be obligatory: 1. That those on whom one spends are poor, having neither money nor earnings. 2. That the one spending has more than what suffices for his own needs. 3. That the one spending is an heir, based on Allah Almighty's saying: (And upon the heir is the like of that).

Obligatory spending includes marrying off a son if he is in need. The father's spending on his son continues until the son becomes self-sufficient through his own earnings. If he becomes capable of earning, his right to maintenance ceases. Mediation is advised before resorting to courts to ensure the father's peace of mind and satisfaction.