Laws of Inheritance (Al-Faraa'id)
Bukhari :: Book 8 :: Volume 80 :: Hadith 735
Narrated Jabir:
While I was sick, the Prophet entered upon me and asked for some water to perform ablution, and after he had finished his ablution, he sprinkled some water of his ablution over me, whereupon I became conscious and said, "O Allah's Apostle! I have sisters." Then the Divine Verses regarding the laws of inheritance were revealed.