Ancestral Property Dispute & On Going Divorce

am asking on behalf of my friend who is in maharashtra. 2 days ago, he was about to sell his ancesteral property, suddenly, a letter was submitted to the society by his wife, on behalf of his son, that not to sell the property without the permission of his son who is 2-4 yr old. History about previous cases: She went, then My friend first put RCR to call her back, she came for 1 day and then later she filed Domestic violence which is going on since 2 years. Wife and her parents came to know about their ancesteral property which was about to sell, so they played. Ancesteral property from his grandfather (Deceased), father (deceased and mother is still living with the guy), this guy (his wife and son not staying with him). Wife father-COP She just wanted to take revenge and MONEY is the issue. Now, can someone guide as how to solve tactfully & protect the property, coz its his wife creating all the chaos? (Amicably tried to resolve marriage dispute, but she denied directly IN RAGE)