Legal rights of wife on property aquired by combined income of both after husband's death

Hello I m a doctor by profession and my husband as well. My father in law have 2 son and 2 daughters . My husband is the youngest child. My husband paid 12.5 lac rs to my father in law for loan after which he transferred 5 acres on my husband's name. My father in law had one 1000 square feet plot and one nine room house on 1500 square feet. After paying 40 lacs to my brother in law they transferred plot on my husband's name. My brother in law got 8 acres, house and 40 lac rs. While we got 5 acres and plot after paying money. Now we built that plot and bought few more properties on income of both of us. All properties are on my husband's name but loan case is combined name. We have 2 daughters. If something happens to me or my husband or both of us what will be succession scenario. My in laws are extremely greedy people they live with us only to extract money and pass that to their other children. I m worried for my babies future. As I don't want our hard earned money to go in wrong hands. My father in law gets very good pension, all money from our farms and rent from our old home while all their medical expenses and daily needs are provided by us. My brother in law is high ranking government officer and his wife also government servant. My both sister in law are married and in very good financial condition.