My husband who needs rights on his father properties .

My father in law proposed an alliance telling that he is widowed (his wife expired )and he had two sons . My family believed that his bought up his son in good manner and he haven't married other women after his wife death .i have married his elder son . Younger one(brother in law) is slow learner and sick . He also informed a lady cook used to come home and help them in food . After my engagement I could notice her involving in all family decisions. After my wedding my father in law spoke to me that the cook lady and him are close friends for 20 years and said they don't have physical relationship . Till then I haven't noticed their behaviors but after this conversation I could find everything different .they have also cheated on my husbands salary package . The lady keeps telling me that she knows all the properties of my father in law and she has guide my husband . She also attends all the family functions and makes her relations to stay in my father in law house . She instructs me in everything and gives decisions to whole family .Now my husband and me are in abroad for his company projects for 2 years . My father in law is 65 years old . Am worried about the family and family properties . Since he and lady knows everything and my husband doesn't know anything . I am worried about this lady involving in all my family decisions . Will she have rights over the property's of my father in law ?