Relatives trying to take land on which shop is from past 25 years

We belong to a Sikh family and live with our mother in law in our parental house on the 1st floor, whereas on the ground floor after several family conflict and property partion our uncle got hold of the ground floor of the same building ,where on the back side of the house my mother in law is running her boutique on the kucha pukka shed from past 25 year which does not cover his land area or his entry at all since she being a widow and her daughter also being a widow she helps her financially. Now we have received a notice from our uncle filing a land encroachment case against us for removing the shop which she is running from past 25 years and is her only means of earning her meal . Request you to please advice what can we do ?? . Since we tried to sort the case outside but he is reluctant to take it to court . Please help !!