Musannaf Ibn Abi Shayba 6:1090

Yazid ibn Harun narrated to us, from Hisham ibn Hassan, from Muhammad ibn Sirin, who said: A woman who used to come to us, who was called Mariyah, told me that she entered upon Ubayd Allah ibn Ma'mar, and with him was a man from the companions of the Prophet, may Allah bless him and grant him peace. That man narrated to Ubayd Allah ibn Ma'mar from the Prophet, may Allah bless him and grant him peace, that a woman came to him with a child of hers and said: "O Messenger of Allah, supplicate to Allah that He may preserve him, for three [of my children] have already passed away." The Messenger of Allah, may Allah bless him and grant him peace, said to her: "Since you have accepted Islam?" She said: "Yes." He said: "A fortified shield against the Fire." She said: Ubayd Allah said to me: "O Mariyah, come and listen to this hadith." She said: I heard it, then I left Ubayd Allah and came to us and narrated it to us.