Musannaf Ibn Abi Shayba 26:56

Waki’ narrated to us, from Sufyan, from Abu Ishaq, from al-Harith, from Ali, who said: A case was brought to him regarding the paternal cousins of one of them, and a maternal brother. Ibn Abbas had given him [the maternal brother] the entire wealth. Ali said: "May Allah have mercy on Abu Abd al-Rahman, for he was indeed a jurist. Had it been me, I would have given him the sixth, and he would have been a partner with them."