Question: A man died when he had to make up for 10 days that he missed in Ramadaan. He had recovered in the month of Shawwaal but he was quite negligent in making up for what he missed. Should his heir fast on his behalf or is this only limited to vow and fasts of expiation? If the heir prefers giving food to fasting, is it permissible? In addition, how many Saa`s (1 Saa`=3 kg. Approx.) of food should be given? Please answer us, may Allaah reward you with the best.
Answer: It is allowable for his heirs to fast the days he missed on his behalf. This is according to the Hadeeth of the Prophet (peace be upon him): If anyone dies in a state (that he had to complete) some days of fasting, his heir must fast on his behalf. The Hadeeth is general and includes the fast of Ramadaan, the fast of vows, and the fast of expiation according to the correct opinion maintained by scholars... read more here.