Musnad Ahmad 626:5

'Abd al-Rahman ibn Mahdi narrated to us, from Sufyan, from Mansur, from Ibrahim, from 'Ubayd ibn Nadilah, from al-Mughirah ibn Shu'bah: That two women, one of them struck the other with a tent pole, and killed her. The Messenger of Allah, peace and blessings of Allah be upon him, decreed the blood money (diyah) upon the paternal relatives ('asabah) of the killer, and for what was in her womb, a slave (ghurrah). The Bedouin said: "Shall I pay blood money for one who neither ate, nor drank, nor cried out? For such as that, it is disregarded." The Messenger of Allah, peace and blessings of Allah be upon him, said: "He speaks in rhymed prose like the rhymed prose of the Bedouins, and for what is in her womb, a slave (ghurrah)."