Musnad Abu Ya'la al-Mawsili 33:1

Al-Abbas ibn al-Walid al-Narsi narrated to us, Abd al-Wahid ibn Ziyad narrated to us, Uthman ibn Hakim narrated to us, Kharijah ibn Zayd narrated to us, from his paternal uncle Yazid ibn Thabit, who said: We went out with the Messenger of Allah, peace and blessings of Allah be upon him, to al-Baqi'. He saw a fresh grave and said, "What is this grave?" They said, "So-and-so, the freedwoman of so-and-so. She died at noon while you were resting, and we disliked waking you." The Messenger of Allah, peace and blessings of Allah be upon him, stood up, and we lined up behind him. He pronounced four takbirs over her, then said, "Let no one die while I am among you except that you inform me." He said, and I think he said, "For my prayer for him is a mercy."