Hadith 1773 - Bab 353 (Prohibition of giving preference to Children over one another in giving Gifts, etc.)
Chapter 18 (The Book of the Prohibited actions)

An-Nu'man bin Bashir (May Allah be pleased with them) said: My father took me to the Messenger of Allah (Peace be upon him) and said to him: "I have gifted one of my slaves to this son of mine." The Messenger of Allah (Peace be upon him) said, "Have you given such gift to every son of yours?" He replied, "No." Thereupon he said, "Take this gift back."

Another narration is: The Messenger of Allah (Peace be upon him) said, "Be mindful of your obligation to Allah and do justice in respect of your children." My father came back and revoked his gift.

Another narration is: The Messenger of Allah (Peace be upon him) asked, "Have you other children besides this one?" He said, "Yes." The Messenger of Allah (Peace be upon him) asked, "Have you awarded a gift like this to all of them." He said, "No." The Messenger of Allah (Peace be upon him) said, "I am not going to bear witness to this act of injustice."

Another narration is: The Messenger of Allah (Peace be upon him) asked, "Do you not except goodness from all of them as you except from him?" He said, "Yes, of course." The Messenger of Allah (Peace be upon him) said, "Then don't do this (i.e., do not give a gift to one son only)."

[Al-Bukhari and Muslim].

Annou"màn Ibn Bashir (das) rapporte que son père l"emmena au Messager de Dieu (bsdl) à qui il dit: «Je viens de donner à mon fils que voici l"un de mes esclaves». Le Messager de Dieu (bsdl) lui dit: «As-tu donné la même chose à chacun de tes autres enfants?» Il dit: «Non». Le Messager de Dieu (bsdl) lui dit: «Reprends ton esclave».