Wills (Kitab Al-Wasaya)
Dawud :: Book 17 : Hadith 2875
Narrated Aisha, Ummul Mu'minin:
A woman said: Apostle of Allah, my mother suddenly died; if it had not happened, she would have given sadaqah (charity) and donated (something). Will it suffice if I give sadaqah on her behalf? The Prophet (peace_be_upon_him) said: Yes, give sadaqah on her behalf.