Sunan an-Nasa'i, Book 45, Hadith 119 (In-Book)

It was narrated that Al-Muhgirah bin Shu'bah said: "A woman of Banu Lihyan struck her co-wife with a tent pole and killed her, and the slain woman was pregnant. The Messenger of Allah ruled that the Diyah was to be paid by the'Asbah of the killer, and that a slave should be given (as Diyah) for the child in her womb".

أَخْبَرَنَا عَلِيُّ بْنُ سَعِيدِ بْنِ مَسْرُوقٍ، قَالَ حَدَّثَنَا يَحْيَى بْنُ أَبِي زَائِدَةَ، عَنْ إِسْرَائِيلَ، عَنْ مَنْصُورٍ، عَنْ إِبْرَاهِيمَ، عَنْ عُبَيْدِ بْنِ نُضَيْلَةَ، عَنِ الْمُغِيرَةِ بْنِ شُعْبَةَ، قَالَ ضَرَبَتِ امْرَأَةٌ مِنْ بَنِي لِحْيَانَ ضَرَّتَهَا بِعَمُودِ الْفُسْطَاطِ فَقَتَلَتْهَا وَكَانَ بِالْمَقْتُولَةِ حَمْلٌ فَقَضَى رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى عَصَبَةِ الْقَاتِلَةِ بِالدِّيَةِ وَلِمَا فِي بَطْنِهَا بِغُرَّةٍ ‏.‏

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