Sa'd bin 'Ubadah (may Allah be pleased with him) asked the Prophet (peace be upon him) about his mother's vow which she was not able to fulfill before she died. The Prophet (peace be upon him) said: "Fulfill the vow on her behalf."

Sa’d bin ‘Ubadah (may Allah be pleased with him) asked the Prophet (peace be upon him),“My mother has died and she did not make a will. Can I give charity on her behalf?”The Prophet (peace be upon him) said,“Yes.”

Sa’d bin ‘Ubadah (may Allah be pleased with him) asked:“My mother has passed away. Will she benefit if I give charity on her behalf?”The Prophet (peace and blessings be upon him) said:“Yes.”Then he said:“The best charity is giving water to drink.”So he (Sa’d) built two cisterns in Madinah.

A woman asked the Prophet (peace be upon him), "My mother passed away without making a will. Can I make a will on her behalf?" The Prophet (peace be upon him) said, "Yes."

It is narrated from Ibn Tawus, may Allah have mercy on him, that "If a person, despite being commanded to make a will, does not make a will, then it is obligatory upon his family to make a will on his behalf."

Tawoos (may Allah have mercy on him) was asked: If a living person gives charity on behalf of a deceased person, how is it? He replied: "It is a very good thing."

It is narrated from Ibn Abbas (may Allah be pleased with them) that "If someone's mother had made a vow for i'tikaf and she passes away, then perform i'tikaf and fast on her behalf."

Aisha (may Allah be pleased with her) observed i'tikaf on behalf of her brother Abdur Rahman after his death.