Abu Dawud and An-Nasa’i narrated on the authority of Ibn ’Abbas that 'Umar (RAA) asked about the judgment of the Prophet (ﷺ) concerning the Diyah of the dead fetus. Hamal bin An-Nabighah Al-Hudhaili then got up and said, “I was between the two women. One of them struck the other with a stone, killing her and what was in her womb. So the Messenger of Allah (ﷺ) ordained....” (as above). Ibn Hibban and al-Hakim graded it as Sahih.

وَأَخْرَجَهُ أَبُو دَاوُدَ, وَالنَّسَائِيُّ: مِنْ حَدِيثِ اِبْنِ عَبَّاسٍ; أَنَّ عُمَرَ ‏- رضى الله عنه ‏- سَأَلَ مَنْ شَهِدَ قَضَاءَ رَسُولِ اَللَّهِ ‏- صلى الله عليه وسلم ‏-فِي اَلْجَنِينِ? قَالَ: فَقَامَ حَمَلُ بْنُ اَلنَّابِغَةِ, فَقَالَ: كُنْتُ بَيْنَ اِمْرَأَتَيْنِ, فَضَرَبَتْ إِحْدَاهُمَا اَلْأُخْرَى.‏.‏.‏ فَذَكَرَهُ مُخْتَصَرًا.‏ وَصَحَّحَهُ اِبْنُ حِبَّانَ, وَالْحَاكِمُ.‏ [1]‏