Can I have my sister in law served with a restraining order?

My husband and I, his younger sister and her husband and my mother-in-law recently bought out the shares of the family business from his older sister and younger brother. Now the older sister-in-law refuses to hand keys, pertinent documents and papers over and is continuing to come onto the premises and cause trouble. I do not want a confrontation with her, she does not belong on the property. What should I do?