Property share for women

Sir/ Madam, My name is Henry, Bangalore. My mom and her sisters are looking for the rules to get their shares in the property (93 Cents = 0.93 Acre) of her parents (which was bought by her grandmother). My mother and her siblings (4 brothers and 3 sisters) wanted to sell their property which belong to their grandmother. My mom brothers asked sisters to sign the documents stating, the property has to be in the name of single person in order to sell. They was not ready to sign, but they were threaten to sign in the document. And, informed my mom and her sisters that they may have to sign again once the property is sold (which never happened till now). Her brothers promised to pay 5L for each one (sister), gave partial amount during 2012 Jan, and confirmed they will give the remaining later once they sold the property. My mom's brothers debate that there is no shares for women in the property as they were married in 1983 and 1984 (Sister 1 and 2 respectively). And, also no rules says that women have equal tights in property. Till now they are not disclose the information, if the property was sold and amount that is worth. The questions I have: 1. Can my mom and her sisters file a case against brothers? 2. Do they eligible for equal shares in property? 3. Do women have rights on property of their grandmother (father's mother)? 4. Can my mom and her sister get the shares in the House which is her parents name?