Islam Property Share To Grandchildren

We have a property in the name of my Paternal Grandfather(Passed away in 1990) He had 2 wives(Late) 1st wife - had only 1 son who is my father (Dies 4 years back). 2nd wife - 3 kids(Younger to my father). 1 son, 2 daughters(Alive). As my father passed away, We would like to get our share from our grandfather's property as my uncle & aunties are not ready to give any share to my father or his kids(me & my younger brother). How can I deal with this and get our share? We approached local jamaath & they are not ready to stand for us as my uncle is a localite (Stays where the property is) & as my uncle is dragging the talks without coming to a solution for more than 4 years now. If the property is 10000 sqft. How it gets divided & what will be our share. Kindly help with your advice to proceed further.