Sunan an-Nasa'i, Book 26, Hadith 91 (In-Book) ⓘ

It was narrated from 'Irak bin Malik that Zainab bint Abi Salamah told him, that Umm Habibah said to the Messenger of Allah: "We have been saying that you want to marry Durrah bint Abi Salamah." The Messenger of Allah said: "As a co-wife to Umm Salamah? Even if I were not married to Umm Salamah, she would not be permissible to me, for her father is my brother through breast-feeding."

أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنْ يَزِيدَ بْنِ أَبِي حَبِيبٍ، عَنْ عِرَاكِ بْنِ مَالِكٍ، أَنَّ زَيْنَبَ بِنْتَ أَبِي سَلَمَةَ، أَخْبَرَتْهُ أَنَّ أُمَّ حَبِيبَةَ قَالَتْ لِرَسُولِ اللَّهِ صلى الله عليه وسلم إِنَّا قَدْ تَحَدَّثْنَا أَنَّكَ نَاكِحٌ دُرَّةَ بِنْتَ أَبِي سَلَمَةَ ‏.‏ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ أَعَلَى أُمِّ سَلَمَةَ لَوْ أَنِّي لَمْ أَنْكِحْ أُمَّ سَلَمَةَ مَا حَلَّتْ لِي إِنَّ أَبَاهَا أَخِي مِنَ الرَّضَاعَةِ ‏" ‏ ‏.‏