Musannaf Ibn Abi Shayba 20:9

Abu Bakr narrated to us, he said: Yahya ibn Ya'la al-Taymi narrated to us, from Mansur, from Ibrahim, from 'Ubayd ibn Nadla, from al-Mughira ibn Shu'ba, he said: The Messenger of Allah (may Allah bless him and grant him peace) decreed the blood money (diya) upon her paternal relatives (aqila), and for the fetus, a slave (ghurra).