I belong to Bangalore. My grandfather had a land which he divided amongst his 2 sons, elder one bein

I belong to Bangalore. My grandfather had a land which he divided amongst his 2 sons, elder one being my father. In his will my grandfather had stated that the younger son should be allowed to use a pathway from the elder son's portion of land to access his house as there was no other access route. Now my uncle has sold his land to a third party. Kindly let me know whether the right of way to the land sold continues as before. Can my father refuse to give access to the third party now? Please note as per will grandfather had given right of passage to my uncle and his family only.