Division of the estate according to the command of Allah is an obligation which it is not permissible to overlook, because Allah, may He be exalted, Himself decided the shares and issued a warning to the one who goes against it. Allah says, after explaining the shares of inheritance (interpretation of the meaning):
âThese are the limits (set by) Allaah (or ordainments as regards laws of inheritance), and whosoever obeys Allaah and His Messenger (Muhammad صلى الله عليه وسلم) will be admitted to Gardens under which rivers flow (in Paradise), to abide therein, and that will be the great success.
14. And whosoever disobeys Allaah and His Messenger (Muhammad صلى الله عليه وسلم), and transgresses His limits, He will cast him into the Fire, to abide therein; and he shall have a disgraceful tormentâ
al-Nisaâ 4:13, 14.
So it is obligatory to advise all the heirs to refer the matter for judgement according to shareeâah, and to divide the wealth as Allah has divided it, and to avoid going against that.
The person who wants to divide the estate has to find out which heirs were alive at the time of death. If the grandmother left behind an estate, you have to find out who was alive at the time of her death: her husband, her father, her mother and her children. With regard to the grandfather, if he died after his wife (the grandmother), then his heirs are: the five sons and five daughters. So the estate should be divided among them, with each male getting the share of two females.
If the grandmother was alive at the time of the grandfatherâs death, then she takes one eighth of her husband's estate, then the remainder is to be divided among the sons and daughters, with each male getting the share of two females.
In this way the share of your father and the share of each of his brothers and sisters may be worked out.
Then if one of the sons died, his estate is to be divided among the living heir.
You said that he left behind three daughters and a wife, in addition to his four brothers and five sisters.
So his estate â which is all that he left behind of wealth, in addition to his share of his fatherâs estate and his motherâs estate â should be divided as follows:
The wife gets one eighth.
The daughters get two thirds.
The rest goes to his brothers and sisters, to be divided among them, with each male getting the share of two females.
If you are confused about the matter, then refer to the scholars in your country.
And Allah knows best.