Is it permissible to fast the expiation for accidental killing on behalf of a deceased person?

Question:
He says: A man was involved in a car accident, and three people died with him. After a period of time, he also passed away, and he was unable to fast the expiation. So, is it obligatory for his heirs after him to fast two consecutive months, or is it not obligatory?

Answer:
The matter returns to the judge if the judge ruled that he is liable for blood money and, for example, for expiation. If the judge in the court ruled that he is liable in this incident and that he was negligent, and that the incident occurred due to his negligence, and that blood money and expiation became obligatory upon him, then there is no doubt that the expiation is obligatory upon him. It is the freeing of a slave, as Allah the Exalted said: . until He said: "But whoever does not find [a slave], then fasting for two consecutive months." So fasting is a substitute for freeing a slave for the one who is unable to do so. This is if the judge ruled that he is liable for the guarantee of blood money and expiation, and he died before performing the expiation. The expiation remains a debt upon him, there is no doubt. If there is a possibility of freeing a slave, such as finding a slave who can be bought and freed, then this is taken from his estate. As for fasting, I do not know that it can be performed by a proxy in such a case. And Allah the Exalted knows best.