It is also narrated from Sayyiduna Imran bin Husain (may Allah be pleased with him) that Sayyiduna Umar (may Allah be pleased with him) said: I beseech by Allah the person who has heard any hadith from the Messenger of Allah (peace and blessings be upon him) regarding the inheritance of the grandfather, to tell me. A man stood up and said: Yes, I was present with the Noble Prophet (peace and blessings be upon him), and he (peace be upon him) gave him (the grandfather) one third share. He (Umar) asked: With which heirs? He replied: That I do not know. He (Umar) said: Then you have not understood.
Hadith Takhrij«اسناده ضعيف لضعف علي بن زيد بن جدعان۔ أخرجه الحميدي: 833، والنسائي في ’’الكبري‘‘: 6336، (انظر مسند أحمد ترقيم الرسالة: 19994 ترقیم بيت الأفكار الدولية: 20236»
Brief Explanation
Benefits: … The share of the true grandfather (jad sahih) is one-sixth, not one-third. However, it is possible that when the true grandfather receives inheritance from two aspects—that is, both as a fixed share (fard) and as a residuary (asaba)—then his total share may become one-third.