It was narrated that Ibn Dhu'aib said: "A grandmother came to Abu Bakr Siddiq and asked him for her inheritance. Abu Bakr said to her: 'You have nothing according to the Book of Allah, and I don't know of any thing for you according to the Sunnah of the Messenger of Allah P.B.U.H. Go back until I ask the people.' So he asked the people and AI-Mughirah bin Shu'bah said: 'I was present with the Messenger of Allah P.B.U.H and he gave her (the grandmother) one sixth.' Abu Bakr said: 'Is there anyone else with you (who will corroborate what you say)?' Muhammad bin Maslamah Al-Ansari stood up and said something like what Mughirah bin Shu'bah had said. So Abu Bakr applied it in her case." "Then the other grandmother, on the father's side, came to 'Umar and asked him for her inheritance. He said: 'You have nothing according to the Book of Allah. The ruling that was passed applied to someone other than you, and I will not make any addi tion to the shares of inheritance. But it is one sixth. If there are two of you then it is to be shared between you, and if one of you is alone then it all belongs to her.'" (Sahih)