Musnad Ahmad 1017:97

Ibn Numayr narrated to us, Abdullah ibn ‘Ata’ narrated to us, from Ibn Buraydah, from his father, who said: A woman came to the Prophet, may Allah bless him and grant him peace, and said: "O Messenger of Allah, I gave a slave girl as charity to my mother, but my mother died and the slave girl remains." He said: "Your reward has been established, and she has returned to you through inheritance." She said: "My mother had a month of fasting upon her; should I fast on her behalf?" He said: "Yes." She said: "My mother did not perform Hajj; should I perform Hajj on her behalf?" He said: "Perform Hajj on behalf of your mother."