(1) After due rights preceding inheritance and in case the said details are true, all the property and wealth of the deceased father will be divided into 144 shares, out of which his wife will receive 18 shares, his mother (your grandmother) 24 shares, the two sons 34-34 shares and the two daughters 17-17 shares.
(2) The property is an inheritance of the father which will be distributed as per the answer 1.
(3) How did he transferred to his wife (your mother), was it sold or gifted? Or there was any other method? Also, whether he kept it in his own possession or gave it in her possession? Please, explain all these points, then in-sha-Allah we shall reply this question. Then, we shall write how much share the grandmother will receive.
Allah (Subhana Wa Ta’ala) knows Best
Darul Uloom Deoband