Property sharing among my husband and my step brother in law

My father-in-law got married twice.my mother-in-law died because of a snake bit .that time my husband was very small,maybe he was in sixth standard I think so.after that my father-in -law married to my step mother-in-law.my father-in-law is having three kids.my husband,my sister-in-law and step brother-in-law.my sister -in-law got married.before my marriage my husband has given everything (whatever he earned)to his father.my father-in -law put that money in the business,construction of house and in buying farming land.nearly 15 lakhs my husband has given to his father.after marriage also he helped his father in so many ways.at the marriage time my husband was not having any property on his name.my husband is35 and my step brother-in-law is23.now problem is that my father-in-law is trying to put some property on my step brother-in -law's name.so we have asked my father-in -law that it is not correct to give any property to your second son.and also we have asked to share all the property..and my father-in-law is not agreeing to share the property.he told us that he will share all the properties after my step brother-in-law's marriage.we don't believe my father in law because he already tried to give one plot(worth 7 lakhs) to his second son.and my father in law is saying that he will give half -half properties to both of his sons...i know that in normal cases it is correct to share the property exactly half-half...but here we are not agreeing for that..because my husband has given so much money to his father.and by using that money he put investment in each and every thing.so my question is that do we have any chance to get more property compared to my step brother in law.how to ask my father in law to give more for us while he is not agreeing for that