Case against son under maintenance act for neglecting parents

My father was a government employee. 18 years ago my father (aged 78) was retired. He has two wife. First wife has one son, one daughter. Second wife has four daughters. First wife has illegal connection with others. so my father married my mother 37 years ago . For some family situation he dint divorce his first wife. My father gave all financial support to study, marriage and everything for his first wife's family. They got all the support from my father till they become rich. His son is now working in abroad, and his daughter is married and well settled. They got everything from my father. I'm second wife's daughter. when my father retired we four are small and not yet finished schooling. Now all are degree holder by my mother. Three daughters are married. we are well maintain our father. my father is very sick. Every month we need around 5k for medicinal expense to my father. His son giving nothing to my father also no any contacts for 15 years. My father shared his property to 6 parts. But first wife needs full property also my fathers pension. Now first wife has filed a case against my father for pension and properties. Is any chance to file a case against his son for my fathers maintenance?