Narrated Ibn Abbas: If a man falls ill during Ramadan and he dies, while he could not keep the fast, food will be provided (for the poor men) on his behalf ; there is no atonement (for his fasts) due from him. If there is some vow which he could not fulfill, his heir must atone on his behalf.
Explanation & Benefits
Shaykh Umar Farooq Saeedi
Benefits and Issues:
➊ The general scholars of hadith hold the view that if there are remaining fasts upon a deceased person, then his guardian should observe the fasts on his behalf.
➋ Abdullah ibn Abbas (radi Allahu anhu) and some other scholars state that in obligatory acts, no one can act as a deputy for another. If a sick person did not deliberately neglect (the obligation) and passed away, then nothing is required of the guardian except to feed (the poor). However, the matter of a vow (nazr) is more stringent because a person has made it obligatory upon himself by his own choice; for this reason, it has also been described as a debt owed to Allah.
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 2401