Sahih al-Bukhari, Volume 8, Book 80, Hadith 754 (USC-MSA) ⓘ
Narrated Anas bin Malik: The Prophet said, "The son of the sister of some people is from them or from their own selves."
حَدَّثَنَا أَبُو الْوَلِيدِ، حَدَّثَنَا شُعْبَةُ، عَنْ قَتَادَةَ، عَنْ أَنَسٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " ابْنُ أُخْتِ الْقَوْمِ مِنْهُمْ ". أَوْ " مِنْ أَنْفُسِهِمْ ".
also referenced under: Book 85, Hadith 39 (In-Book) & Hadith 6762 (DarusSalam)