Sunan Sa'id

Sayyiduna Ali (may Allah be pleased with him) said: "Regarding the child of the woman who performed li'an (i.e., whose mother did li'an), who died and left behind his mother and brother, the brother should be given one-sixth, the mother one-third, and whatever remains should be returned to them according to their shares." And Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: "The brother gets one-sixth and the rest is for the mother, and the mother is his 'asaba (residuary heir)." And Sayyiduna Zaid bin Thabit (may Allah be pleased with him) said: "The mother gets one-third, the brother one-sixth, and the remainder is for the Bayt al-Mal (public treasury)."