Sayyiduna Umar bin Khattab (may Allah be pleased with him) wrote to Sayyiduna Abu Musa Ash’ari (may Allah be pleased with him):“We used to give the grandfather one-sixth along with the brothers, and perhaps we were excessive with him in this. So when this letter of mine reaches you, give the grandfather half with one brother, a third with two brothers, and if the brothers are more, do not make the grandfather’s share less than a third.”