مسائل المنتخبه (Articles Of Islamic Acts) - الخوئي، السيد أبوالقاسم - الصفحة ٥٨٩ - ٢ to the granddaughter

grand father and grandmother and the paternal grandfather gets twice as much as the paternal grandmother. And if the heirs of the dead person are her husband and her paternal or maternal grandfather and grandmother, the husband gets half of the property and the grandfather and the grandmother get their inheritance in the manner mentioned in the previous Articles.
٢٧٦٣. There are a few ways of combination of brother or sister or brothers or sisters with paternal grandfather or paternal grandmother or maternal grandfather or maternal grandmothers or paternal or maternal grandfathers and grandmothers:
(i) That the maternal grandfather or grandmother and brother or sister are from the mothers side. In that event the property is divided among them equally though they are of different sex.
(ii) That with paternal grandfather or grandmother the brother and sister are from the side of the mother. In that case also the property is divided among them equally provided that all of them are males or all of them are females. And in case they are different every male gets twice as much as the female.
(iii) That with the paternal grandfather or the grandmother the brother or sister are from the side of mother and father. The order applicable in the previous case also applies in the present case. And it should be remembered that if the paternal brother or sister of the dead person is combined with real brother of sister those who are paternal do not inherit alone, but all of them inherit.
(iv) That there are paternal or maternal grandfathers or grandmothers whether.all of them are males or females or they are different and similarly there are maternal and paternal brothers and sisters. In this case ١/٣ of the inheritance is for the maternal relatives and it is.divided equally among them although they may be different as regards sex. And ٢/٣ of the inheritance is for the paternal relatives, among whom every male gets twice