Do the children and the mother bear a sin if the father spends on them from unlawful usurious bank money, and what must they do if a part of this money returns to them, and is money earned from work in Saudi Arabia considered unlawful if the father paid for travel expenses from usurious money?

The children of a usurer are not sinful if they eat from his usurious money, or wear clothes bought with it, or travel with it, provided they have no other means of livelihood. They should advise their father through methods they deem beneficial. However, if other means of livelihood become available to them, or if they do not need this money for their essential life necessities, they are obligated to dispense with it.

If the usurer father passes away, the heirs are obligated to dispose of the usurious money by returning it to its rightful owners if they are known. Otherwise, they should donate it to general and specific charitable causes. If it is difficult for them to determine the exact usurious amount, they should divide it into two halves, taking one half and distributing the other half.