(19) بَابُ بِرِّ الْوَالِدَيْنِ بَعْدَ مَوْتِهِمَا
Ibn 'Abbas reported that a man said, "Messenger of Allah, my mother diedwithout a will. Will it help her if I give sadaqa on her behalf?""Yes," he replied.
Reference: Al-Adab Al-Mufrad 39
In-book reference: Book 1, Hadith 39
English translation: Book 1, Hadith 39