"She is the daughter of my brother through breast-feeding, and what becomes unlawful (for marriage) through breast-feeding is the same as that which becomes unlawful through lineage."
أَنَّ رَسُولَ اللَّهِ ﷺ أُرِيدَ عَلَى بِنْتِ حَمْزَةَ فَقَالَ إِنَّهَا ابْنَةُ أَخِي مِنَ الرَّضَاعَةِ وَإِنَّهُ يَحْرُمُ مِنَ الرَّضَاعِ مَا يَحْرُمُ مِنَ النَّسَبِ