share first wifes son passed away now his wife coming and giving a co

hello sir, before 20 years my grand mother buy a land with building landlord passed away he had two wifes , first wife had one son, she passed away when his son was the age of 6yrs then the landlord married second wife and she had one daughter, some years later first wifes son married a girl without fathers permission in other caste and he is not also having good habits so his father gave him some money and told you are having any rights in my self owned property and he also mentioned that in deed and also mentioned that property is only for his second wife and daughter and the father also passed away then, that daughter sold the land to my grandmother before 20 years for the past five years that first wifes son and his wife coming with police yearly twice giving complaint to CM cell and Collector that we purchase a land without their knowledge and we cheated them and they are asking the house or share first wifes son passed away now his wife coming and giving a complaint on us before