Musnad Ahmad 1165:8

Yahya ibn Abi Bukayr narrated to us, he said: Isra’il narrated to us, from Simak, from Qabus ibn Abi al-Mukhariq, from Umm al-Fadl, she said: I saw as if there was a limb of the limbs of the Messenger of Allah, may Allah bless him and grant him peace, in my house. She said: I was distressed by that, so I came to the Messenger of Allah, may Allah bless him and grant him peace, and mentioned that to him. He said: "You saw good. Fatimah will give birth to a boy, and you will nurse him with the milk of your son, Qutham." She said: So she gave birth to al-Hasan, and I was given him, and I nursed him until he moved, or I weaned him. Then I brought him to the Messenger of Allah, may Allah bless him and grant him peace, and he sat him in his lap. He urinated, so I struck between his shoulders. He said: "Be gentle with my son, may Allah have mercy on you—or: may Allah set you right—you have hurt my son." She said: I said: O Messenger of Allah, take off your lower garment and wear another garment so that I may wash it. He said: "The urine of a female infant is washed, and the urine of a male infant is sprinkled [with water]." *** Abdullah said: I found in my father’s book: Abu Ma’mar narrated to us—and I heard it myself from Abu Ma’mar—he said: Abdullah ibn Idris narrated to us, he said: Yazid—meaning ibn Abi Ziyad—narrated to us, from Abdullah ibn al-Harith, from Umm al-Fadl bint al-Harith, who is the mother of the children of al-Abbas and the sister of Maymunah, she said: I came to the Prophet, may Allah bless him and grant him peace, during his illness, and I began to weep. He raised his head and said: "What makes you weep?" I said: We fear for you, and we do not know what we will encounter from the people after you, O Messenger of Allah. He said: "You are the oppressed ones after me."