Making up the fast for a deceased person who left off fasting Ramadan for years

Question:
Honorable Shaykh, may Allah grant you success. This questioner says: My father has passed away, and it was his habit that he did not fast in Ramadan. Then, in the last two years of his life, may Allah have mercy on him, he fasted. The period he did not fast is estimated to be about forty years. Their question is: What should be done? Do we fast on his behalf? Or what do we do?

Answer:
I do not know what the obstacle is that prevents him from fasting, or whether he is able to fast but is negligent. The fast remains a debt on him. As for the one who dies with fasting owed to him, this is the hadith: . If he has several guardians, they may divide it among themselves, and there is no harm in that. Yes.