Sahih al-Bukhari, Hadith 2644 ⓘ
Narrated Aisha: Aflah asked the permission to visit me but I did not allow him. He said, "Do you veil yourself before me although I am your uncle?" `Aisha said, "How is that?" Aflah replied, "You were suckled by my brother's wife with my brother's milk." I asked Allah's Messenger about it, and he said, "Aflah is right, so permit him to visit you."
حَدَّثَنَا آدَمُ، حَدَّثَنَا شُعْبَةُ، أَخْبَرَنَا الْحَكَمُ، عَنْ عِرَاكِ بْنِ مَالِكٍ، عَنْ عُرْوَةَ بْنِ الزُّبَيْرِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتِ اسْتَأْذَنَ عَلَىَّ أَفْلَحُ فَلَمْ آذَنْ لَهُ، فَقَالَ أَتَحْتَجِبِينَ مِنِّي وَأَنَا عَمُّكِ فَقُلْتُ وَكَيْفَ ذَلِكَ قَالَ أَرْضَعَتْكِ امْرَأَةُ أَخِي بِلَبَنِ أَخِي. فَقَالَتْ سَأَلْتُ عَنْ ذَلِكَ رَسُولَ اللَّهِ صلى الله عليه وسلم فَقَالَ " صَدَقَ أَفْلَحُ، ائْذَنِي لَهُ " .
also referenced under: Book 52, Hadith 8 (In-Book) & Volume 3, Book 48, Hadith 812 (USC-MSA)