Is a man obligated to support his grandchildren?

A man must financially support his children and grandchildren. The financial support of a child is obligatory upon the father. If the father is poor or deceased and the mother is wealthy, then the financial support becomes obligatory upon the mother. As for grandchildren, their financial support is obligatory upon the grandfather if they are poor and the grandfather is wealthy. This is because the terms "children" (أولاد) and "sons" (أبناء) encompass them in religious texts, such as the Almighty's saying: (Allah instructs you concerning your children) and the Prophet's hadith about Al-Hasan: (Indeed, this son of mine is a master).