Sunnah.com reference : Book 8, Hadith 194English translation : Book 8, Hadith 1141Arabic reference : Book 8, Hadith 1130
Narrated ['Aishah (RA)]:
Aflah (her foster suckling uncle), brother of Abul-Qais, came and asked her permission to enter after the Hijab (was instituted for women). She said, "I refused to allow him in and when Allah's Messenger (ﷺ) came, I told him about what I had done, so he commanded me to give him permission to enter where I am and said, 'He is your paternal uncle.'"

[Agreed upon].
وَعَنْهَا: { أَنْ أَفْلَحَ ‏-أَخَا أَبِي الْقُعَيْسِ‏- جَاءَ يَسْتَأْذِنُ عَلَيْهَا بَعْدَ اَلْحِجَابِ.‏ قَالَتْ: فَأَبَيْتُ أَنْ آذَنَ لَهُ, فَلَمَّا جَاءَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-أَخْبَرْتُهُ بِاَلَّذِي صَنَعْتُ, فَأَمَرَنِي أَنْ آذَنَ لَهُ عَلَيَّ.‏ وَقَالَ: 
"إِنَّهُ عَمُّكِ".‏ }  مُتَّفَقٌ عَلَيْهِ .‏  1‏ .‏‏1 ‏- صحيح.‏ رواه البخاري (2644)‏ وأطرافه، ومسلم (1445)‏ وفي سياقه من الحافظ نوع تصرف.‏