Ja'far bin Muhammad narrates from his father that Sayyidah Umm Kulthum bint Ali (may Allah be pleased with them both) and her son Zayd bin Umar bin al-Khattab died on the same day, and it could not be known which of them died first; so she did not inherit from him, nor did he inherit from her. Likewise, the martyrs of the Battle of Siffin and of the Event of al-Harrah did not inherit from one another. The chain of this hadith is sahih (authentic). It contains points of benefit, one of which is that Sayyidah Umm Kulthum (may Allah be pleased with her) bore Sayyiduna Umar (may Allah be pleased with him) a son; and for the other point of benefit there is a supporting narration: