Answer
(Fatwa: 630/611/N=1433)
At the time of your grandmother’s death, if her husband (your grandfather) was not alive then the house left by her shall be divided into 16 shares, after due rights proceeding inheritance. Out of which your mother shall get 8 shares (i.e. half of the house), 2-2 shares shall go to all three brothers of your deceased grandmother each and 1-1 share to each of her alive sisters. And the deceased brothers and sisters shall get no shares from it. The detail of the division is as follows:
Details:
Daughter: 1×8 = 8
Alive Brothers: 3×2 = 6
Alive Sisters: 2×1 = 2
Total: 16 shares
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband