Musannaf Ibn Abi Shayba 26:118

Waki’ narrated to us, from Sufyan, from Salamah ibn Kuhayl, from Abu Sadiq, that a man asked Ali about a woman whose sister died, and her mother was a slave. Ali said, "Does the sixth [share] encompass her neck?" He said, "No." He said, "Leave us be regarding her for the rest of the day."