(2) باب وُصُولِ ثَوَابِ الصَّدَقَاتِ إِلَى الْمَيِّتِ
A'isha (Allah be pleased with her) reported that a man said to Allah's Apostle (ﷺ):
My mother died all of a sudden, and I think if she (could have the opportunity) to speak she would have (made a will) regarding Sadaqa'. Will I be entitled to reward if I give charity on her behalf? He (the Holy Prophet) said: Yes.
Reference: Sahih Muslim 1004 c
In-book reference: Book 25, Hadith 17
USC-MSA web (English) reference(deprecated numbering scheme): Book 13, Hadith 4002