Share of daughter in Mother's ancestral property

This question is for my relative Madam. Her father had a property. She and her sister are only 2 daughters. It was given on rent after their father's dead. Tenant filed a case not vacating and only elder daughter (my relative madam) fought (with help of her son) and won the case in Madurai High Court. Now her sister's son (sister died) came and struggling for major part of property. So she failed again for equal division of property (Will was written but it is unregistered). Property is under the control of elder daughter (my relative madam). She (actually her son) pays property tax. Now the issue is daughter of this lady (my relative madam). Actually she wants to give to her son as he takes care of her, he only spend for earlier case and now for the current case. But her daughter fights to have more share (actually daughter did love marriage. Hence no jewels and other stuff given). She brings some politicians of that area to relative Madam's home Feeling bad on her. What she can do now. She is around 78 now. Even ancestral property is not equally and legally divided. Her daughter is demanding equivalent money now itself. please advice to help her.