Is a woman whose husband has passed away obligated to financially support her children, and does this support include housing, in the event that the deceased husband's father is alive? And how is this support determined?

The maintenance of poor grandchildren who have no wealth or income is obligatory upon their grandfather, provided certain conditions are met. These conditions include the maintenance being surplus to his own needs, those of his wife, and his dependents. If there is another wealthy heir, such as the mother, the maintenance is divided between the grandfather and the mother according to their inheritance shares. Thus, according to the Hanbalis and Hanafis, the mother is responsible for one-sixth and the grandfather for the remainder. As for the Shafi'is, they hold that the entire maintenance is the grandfather's responsibility. Housing is part of maintenance, and the assessment of maintenance and housing, in case of dispute, falls within the jurisdiction of the judiciary.