Is it obligatory on a man's eldest son to give the Qadha of his fast and prayers after his death?
Answer
If a person did not offer some of his obligatory prayers, and did not care to give Qadha, in spite of being able to do so, after his death, it is not necessary upon the eldest son to perform the Qadha. If he missed prayers and cared about performing Qadha but he failed to do so, the eldest son should perform the Qadha or he may hire someone to perform them. The Qadha prayers of his mother is not obligatory upon him, though it is better if he performs them.