Sunan Abi Dawud
Sunan Abi Dawud 376
Mujahid bin Musa and 'Abbas bin 'Abd al-'Azim al-'Anbari—the wording is the latter's—said: Narrated to us 'Abd al-Rahman bin Mahdi, narrated to me Yahya bin al-Walid, narrated to me Muhill bin Khalifah, narrated to me Abu al-Samh, who said: I used to serve the Prophet (ﷺ). Whenever he intended to take a bath, he would say: "Turn your back towards me." So I would turn my back toward him and conceal him with it. Then Al-Hasan or Al-Husayn (may Allah be pleased with them) was brought to him, and he urinated on his chest. I came to wash it, and he said: "Water is to be washed from the urine of a female child, and sprinkled from the urine of a male child." 'Abbas said: Yahya bin al-Walid narrated to us. Abu Dawud said: He is Abu al-Za'ra'. Harun bin Tamim said on the authority of Al-Hasan: All urines are alike.