Sahih Muslim Book 008, Hadith Number 3401.

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

'Aisha (Allah be pleased with her) reported: My foster uncle came to me and sought permission (to enter the house), but I refused him permission until I had solicited the opinion of Allah's Messenger (May peace be upon him). When Allah's Messenger (May peace be upon him) came, I said to him: My foster-uncle sought my permission to (enter the house), but I did not permit him, whereupon Allah's Messenger (May peace be upon him) said: You better admit your uncle (into the house). I ('Aisha) said: It was the woman who suckled me and not the man. (But he) said: He is your uncle, admit him.

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