Abdullah bin Buraydah al-Aslami (may Allah have mercy on him) narrates from his father (Sayyiduna Buraydah, may Allah be pleased with him) that he said: I was with the Prophet (peace and blessings be upon him) when a woman came and said: O Messenger of Allah! I gave a slave girl to my mother in charity; my mother has died and the slave girl remains. He (peace and blessings be upon him) said: "Your reward is established, and the slave girl has returned to you through inheritance." Then she said: She has died and she owed a month of fasting! He (peace and blessings be upon him) said: "Fast on behalf of your mother." Then she said that she had also not performed Hajj, and he (peace and blessings be upon him) said: "Perform Hajj on behalf of your mother."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7635