Fatwa ID: 02480
Answered by: Maulana Maruf Ahmed
Due to my father's diabetic condition and old age he is not able to fast in ramadan. Is there some kaffara/compensation that he has to give.
بسم الله الرحمن الرحي
If your father is chronically ill such that there is no hope of recovery, he needs to pay fidya. More details can be found on the following link:
However, if it is an illness from which he has hope of recovering, then he simply performsqadha of missed fasts once he is able to. 
And only Allah knows best.
Maulana Maruf Ahmed
Checked and approved by Mufti Mohammed Tosir Miah
Darul Ifta Birmingham