Sahih Bukhari

Narrated Ibn `Abbas:That the mother of Sa`d bin Ubada the brother of Bani Saida died in Sa`d's absence, so he came to the Prophet saying, ""O Allah's Messenger (ﷺ)! My mother died in my absence, will it benefit her if I give in charity on her behalf?"" The Prophet (ﷺ) said, ""Yes."" Sa`d said, ""I take you as my witness that I give my garden Al-Makhraf in charity on her behalf