Dispute ragarding grandfather property

i am having a property of my grandfather in MP. My grandfather is dead 4 months ago. I am not sure that my grandfather has given will against the property or not. My father has 1 brother and 1 sister. If my grandfather has given property to my father's brother & sister. than i being his grandson can question against the will. And if the will is not given by grandfather, than my father can question his will or not.

Kindly reply as soon as possible.

SIMRAN SINGH

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