Seek your help

My forefather had purchased a land in Azamgarh district, U P. My granfather had 2 brothers, out of which 1 died. Since the land was not used by his brother (name - NS)for faming/ building purpose, my grandfather,after having a verbal consent with his brother ( that he is not having any problem if my granfather uses the land to build a house )built a house ( 3 rooms upstairs and 7 romms downstairs for commercial use) with the help of his PF & gratuity amount post-retirement. Also, NS and his family has not contributed a single penny to build this house. Afte the completion of the house, within 2 years , NS and his family started demanding for the rooms upstairs & shops downstairs mentioning that their land is used to build this house and this ended up to quarrels everyday. My grandfather & grandmother were staying alone there and had no option but to give a room upstair and a shop downstair. Gradually they started demanding for another room upstairs & forcefully locked a shop downstairs. My garndfather died last year and everything has come on father. Todays scenario is they have forcefully locked 4 shops downstairs and 2 rooms upstairs. It seems they are planning to capture the entire house, wherein they have not spent a single penny to build it. What can be done in these circumstances?? Can we opt for stay order, if yes, what is the process??