Remedy as father's brother claims whole property of grandmother

My father sold his agricultural land to his brother long ago. There's an agricultural land self acquired by my paternal grandmother in her name and now she's no more. Now my father's brother is unwilling to give share of my grandmother to my father. As my father's brother purchased my father's land. My father's brother is claiming falsely that he also acquired my father's share of my grandmother's land. He is showing a paper as a proof where my father wrote that he sold his property for so so amount.the said land is being cultivated by my father's brother as we live in some other city far away from my native village. Even sisters of my father expressed their consent to share the land equally between two brothers whereas my father's brother is claiming the whole land. can my father file a case against his brother??