Sahih Bukhari Volume 3, Book 41, Hadith Number 603.

Narated By ‘Aisha : Abu bin Zam’a and Sad bin Abi Waqqas carried the case of their claim of the (ownership) of the son of a slave-qirl of Zam’a before the Prophet. Sad said, “O Allah’s Apostle! My brother, before his death, told me that when I would return (to Mecca), I should search for the son of the slave-girl of Zam’a and take him into my custody as he was his son.” ‘Abu bin Zam’a said, ‘the is my brother and the son of the slave-girl of my father, and was born or my father’s bed.” The Prophet noticed a resemblance between Utba and the boy but he said, “O ‘Abu bin Zam’a! You will get this boy, as the son goes to the owner of the bed. You, Sauda, screen yourself from the boy.”