Will Property

Namaskar, Our grandmother, my father and uncle partitioned the agriculture properties in the year 2001 with registered partition deed. And wrote in the partition deed like after death of grandmother her property should share equally with 2sons. But after some yrs my uncle was not taken care of her and grandmother made registerd will including houses at that property to my name {grand son} as we taking care of her. In the year 2012 grandmother died till now we are not executed the will as I got know about the will in last month, property katha and rtc title still running in the name of grandmother. But my farther and uncle are equally in physical position.. can I claim this successfully.. how I can I proceed please let me know.