right on my ancestral property

3rd Party gave his property by GPA to your grandfather who sold it to your father, the property thus became property of your father as he directly acquired it by Sale. You as grandson has no right in the property of your father during his lifetime.

my grandfather has 3son and 3daughter, I am the daughter son, 3rd Party gave his property by GPA to your grandfather who sold it to his son because GPA property cannot be divided within them & he told he will divide , now my grandfather is dead they say it's registered in their name so it's their property but actually reason was to make it divide to all after registration. now they have thrown my grandmother out and saying it's their property. how could we fight by any way son or daughter or my grandmother have power on it