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كتاب الشهادات
52  
Witnesses
(7)
Chapter: To give witness concerning lineage, foster suckling relations and dead persons
(7)
باب الشَّهَادَةِ عَلَى الأَنْسَابِ وَالرَّضَاعِ الْمُسْتَفِيضِ وَالْمَوْتِ الْقَدِيمِ
Sahih al-Bukhari 2645

Narrated Ibn `Abbas:

The Prophet (ﷺ) said about Hamza's daughter, "I am not legally permitted to marry her, as foster relations are treated like blood relations (in marital affairs). She is the daughter of my foster brother."

حَدَّثَنَا مُسْلِمُ بْنُ إِبْرَاهِيمَ، حَدَّثَنَا هَمَّامٌ، حَدَّثَنَا قَتَادَةُ، عَنْ جَابِرِ بْنِ زَيْدٍ، عَنِ ابْنِ عَبَّاسٍ ـ رضى الله عنهما ـ قَالَ قَالَ النَّبِيُّ صلى الله عليه وسلم فِي بِنْتِ حَمْزَةَ ‏ "‏ لاَ تَحِلُّ لِي، يَحْرُمُ مِنَ الرَّضَاعِ مَا يَحْرُمُ مِنَ النَّسَبِ، هِيَ بِنْتُ أَخِي مِنَ الرَّضَاعَةِ ‏"‏‏.‏
Reference : Sahih al-Bukhari 2645
In-book reference : Book 52, Hadith 9
USC-MSA web (English) reference : Vol. 3, Book 48, Hadith 813
  (deprecated numbering scheme)