Property in mother-in-laws name

Hi, My father-in-law who is about 70 yrs old was born in a wealthy family but he lost all his property(even before his kids were born later whatever money he had he lost by investing in business) and is now without a penny. He has got 3 kids 2sons and 1daughter my husband being youngest. The eldest son is married and has a son of about 6 years but since he has differences with his wife has been living separately since 5-6years(but not divorced) The daughter is also married and has a son of 16 years husband is a drunkard and she is working and taking care of her family. My husband is posted in North India all along his service of 17 years. The entire financial responsibility of parents is taken care of my husband. My in-laws stay in a leased house 3/4th of amount paid by my husband. For their monthly expenditure before marriage he used to put money in his sisters a/c(since she stays close to my in-laws house) after marriage i.e 4years earlier he invested a lump sum money with a friend who is giving them entire interest. Few years before marriage my husband bought a site in his mothers name. My mom-in-law is a heart patient who had an heart attack in 2008 but she recovered now again she has had a major heart attack wherein doctors have said her survival is difficult. Since she has not made any Will, will my husband get back his property in his moms name? Can his sister or brother claim this property? And since he has financially supported them for 17 yrs what about other movable assets which my mom-in-laws have can he claim it? P.S My husbands brother in no way has helped or supported his parents. My husbands sister stayed close to her parents and gave them emotional support. Regarding hospital charges since my husband is a central govt employee its taken care of govt. Plz advice