Sahih Muslim Book 8, Hadith Number 3404.

Chapter: Kitab Al-Rada’a-Book pertaining to fosterage.

‘Aisha (Allah be pleased with her) reported: My foster-uncle Abu’l Ja’d (kunya of Aflah) sought permission from me, which I refused. (Hisham said to me that Abu’l-Ja’d was in fact Abu’l-Qu’ais). When Allah’s Apostle (May peace be upon him) came, I (‘Aisha) informed him about it. He said: Why did you not permit him? Let your right hand or hand be besmeared with dust.