Maliks Muwatta Book 36, Hadith Number 53.

Malik related to me from Hisham ibn Urwa from his father from A’isha, the wife of the Prophet, may Allah bless him and grant him peace, that a man said to the Messenger of Allah, may Allah bless him and grant him peace, “My mother died suddenly, and I think that had she spoken, she would have given sadaqa. Shall I give sadaqa for her?” The Messenger of Allah, may Allah bless him and grant him peace, said, “Yes.”