Widow Daughter in law questioning will

My brother was staying in native with his wife for 10 years. He died in an accident. I moved my brothers family(wife and 2 children) to City with the intention of giving good education to his children. its been 10 years now. My brothers kids are doing graduation now and I have been paying their college fees. My father has made a registered will to his self acquired properties. According to WILL, all the properties will go to my mother first and after her demise, properties will be given to me and my brothers family. The city house(where we are all staying)has been given to me and all the property at native to my brothers family. My father died 4 years back. My mother was collecting all the rents and managing my brothers family in 1st floor. I have renovated the entire city house and have constructed second floor. My sister in law is harassing my mother and me to give equal share in the city house and giving threats. She has harassed so much that my mom has got health complications(B P and Heart problems). She is staying with me in 2nd floor. My sis in law has occupied the whole 1st floor and many of her relatives are staying with her. I have been requesting her to leave the house and take ownership of the property given to her. She is reluctant to leave the house.