"I said: 'O Messenger of Allah, there is a man asking permission to enter your house.' The Messenger of Allah said: 'I think it is so-and-so the paternal uncle of Hafsah through breast-feeding.' 'Aishah said: If so-and-so (her own paternal uncle through breast-feeding) were alive, would he be allowed to enter upon me?' The Messenger of Allah said: 'What becomes unlawful (for marriage) through breast-feeding is that which becomes unlawful through birth.'"
Sunan an-Nasa'i Book 26, Hadith 118
← Previous Hadith "Aishah said: 'The Messenger of Allah entered upon me and there was a man sitting with me. He got upset about that, and I saw the anger in his face.' I said: "O Messenger of Allah, he is my brother through breast-feeding." He said: "Be careful who you count as your brothers" --or: "be careful who you count as your brothers through breast-feeding"-- "for the breast-feeding (which makes marriage prohibited) is from hunger."

Sunan an-Nasa'i Book 26, Hadith 117 Next Hadith → "My paternal uncle through breast-feeding, Abu Al-Ja'd, came to me, and I sent him away. -He (one of the narrators) said: "Hisham said: 'He was Abu Al-Qu'ais." - "Then the Messenger of Allah came, and I told him. The Messenger of Allah said: 'Give him permission (to enter).'"

Sunan an-Nasa'i Book 26, Hadith 119