1) you can move court and obtain an order directing your son and daughter in law to vacate your house .
2) you can also move the HC to direct City Superintendent of Police to enquire into the matter in respect of complaint filed by you and seeking protection of life and liberty from son and daughter in law.
3) you can also move senior citizen tribunal and obtain order for payment of maintenance by your son
4) you can also make a will wherein you bequeath your property to whomsover you desire . mention reasons why you dont want to bequeath house to your son