What is the Sharia ruling on dealing with an eighty-year-old father who claims to be fasting while he is not, and his children fear confronting him to avoid problems? Is it permissible for them to pay the expiation of feeding a poor person on his behalf for each day, knowing that he has done this in previous Ramadans?

If a person is of sound mind and capable of fasting, then it is obligatory upon him. If he breaks his fast, he must make up for it (qada'), and feeding the poor (fidya) is not sufficient. However, if he is unable to fast due to old age or an illness from which recovery is not expected, then he must feed one poor person for each day he misses. Feeding the poor on his behalf during his lifetime without his permission is not sufficient. The evidence for this is Allah's saying: "And upon those who are able to fast, but with difficulty, is a ransom: the feeding of a poor person." Ibn Abbas interpreted this as a concession for the elderly man and the elderly woman who are unable to fast. The amount of feeding is one mudd of food (approximately 750 grams) for each day. It is permissible to feed thirty poor people at once, or one poor person over thirty days. Whoever knows of his situation should gently advise him. If he responds, then that is well and good. Otherwise, the advisor is not obligated to guide him.