Is it permissible for a father to take from his son's money to repair his car or to buy goods for his business, even though he spends his money on smoking? And is it permissible for the son to demand his money back as a debt, or to hide his money from him through dissimulation?

A father may take from his son's wealth under certain conditions. Accordingly, a father does not have the right to take from his son's wealth if the son is in need of it for marriage, and the father is not in need and has a profession from which he earns a living. The son is not obliged to give it to him. However, the son must treat his father kindly and gently. Furthermore, it is not permissible to assist the father in purchasing cigarettes, because it is assisting in a forbidden act. It is permissible for the son to give his father money as a debt owed by him, and the majority of scholars permit demanding repayment of this debt. It is also permissible for the son to conceal money from his father using ma'arid (euphemisms or indirect statements).