It is narrated from Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said concerning the urine of a nursing infant: "Water is to be sprinkled on the urine of a boy, and the urine of a girl is to be washed (clean)." This hadith is sahih (authentic) on the condition of Imam Bukhari and Imam Muslim, but the two Shaykhs did not record it.

Lubabah bint al-Harith (may Allah be pleased with her) narrates that Sayyiduna Husayn (may Allah be pleased with him) urinated in the lap of the Prophet (peace and blessings be upon him). I said: "Give me your garment so that I may wash it." He (peace and blessings be upon him) said: "The urine of a girl is washed, and water is sprinkled on the urine of a boy."

Abu al-Samh (may Allah be pleased with him) narrates: I was the servant of the Prophet (peace and blessings be upon him). Sayyiduna Hasan or Husayn (may Allah be pleased with them both) was brought, and he urinated on his (peace and blessings be upon him) chest. The people began to wash it, but he (peace and blessings be upon him) said: "Just sprinkle water on it, for the urine of a girl is washed and water is sprinkled on the urine of a boy." The two Shaykhs mentioned pouring water over a boy's urine, but the distinction regarding a girl's urine is not mentioned in their narrations.