How is the grandfather's estate distributed Islamically, if the father and paternal uncle died before the division of the inheritance, and the paternal uncle has no children?

If the grandfather passed away, leaving only two sons and one daughter, the inheritance is divided among them according to the rule: "for the male, what is equal to the share of two females." Thus, the inheritance will be five shares: two shares for each son, and one share for the daughter. If one of the sons then passes away, leaving only a wife, she receives one-fourth of his inheritance. If his brother (the questioner's father) and sister were alive at the time of his death, the remainder goes to them by ta'sib (agnatic succession), with the male receiving a share equal to that of two females. The share of the questioner's father must then be divided among his own heirs. We emphasize the seriousness and complexity of inheritance matters, and that it is not sufficient to rely merely on a fatwa; rather, the case must be brought before the Shar'i courts for investigation to ensure that there are no wills, debts, or other rights that take precedence over the heirs' entitlement.