Had a car accident and had to break

Q: My father died and did not make up for some missed days of Ramadan of the year 1400 A.H. I do not know the number of days missed. The days missed were not due to illness, rather he broke his Sawm (Fast) while he was traveling and feeling tired. The next Ramadan came and my father did not make up for the missed days of the previous one. I told him of the matter and he replied that he will make them up in the winter. However, he died due to a car accident and I am sure that he did not make up for these days. I ask you to guide me; what should I do? Should I fast these days or give Sadaqah (voluntary charity) on his behalf, for he left considerable wealth?

(Part No. 10; Page No. 376)  A: It is permissible for you to observe the fast of the days you think your father did not make up for, for the general meaning of the Prophet's saying: If anyone dies in a state (that he had to complete) some days of fast, his heir must fast on his behalf. Reported by Al-Bukhari and Muslim. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.