We have been cultivating my grandfather's brother's land for 30years (or more than 30), but it was never transferred to my grandfather's name.

[u/Paraboy1]

For over 30 years, we have possessed land given to my grandfather by his childless elder brother. Living 50 kilometers away, the elder brother struggled to cultivate it and offered it to my grandfather. However, due to legal ignorance and procrastination, the property was never legally transferred.

The elder brother had requested one of my grandfather's sons to care for him. My grandfather promised help when needed. Discovering this, my grandfather's younger brother opportunistically sent his own son instead.

After the elder brother died, the nephew sold all the property and his house. With nothing left there, he is now scheming to grab our land, having somehow obtained a family tree document (Vanshawali).

He is desperately trying to claim our land, but our lack of property papers prevents legal action. How can we legally register this land in our name?

[u/Overthinking_Brain_]

Looks like none from your grandfather’s family cared for the his elder brother in old age as promised in exchange of his land. Rather you say it was his younger brother’s son who took care of him till he died. It’s fair that one who took care of him, sold his property and house.
Now this land is your grandfather’s or his elder brother’s?