Fast on behalf of the deceased

Q 2: My father died and he missed some days of fasting during Ramadan. After finishing the mourning period, my mother made up for these missed days on behalf of my father. Is this act permissible or not? Can any of my father's relatives make up for these days on his behalf? Please answer me, may Allah reward you with the best. (Part No. 9; Page No. 66

A: This is a good deed and it is enough that your mother made up for the days of Sawm (Fast) her husband missed in Ramadan. May Allah multiply her reward and bless you.May Allah grant us success. May Peace and blessings of Allah be upon our Prophet Muhammad, his family and Companions.