Brother damaging reputation of sister and father

I need urgent advice on this please. My brother out of frustration to get his share of property at the earliest is spreading false information about my father. He approached CBI, income tax dept, airport authority of India (my father worked there and retired in 2009), media, police, health ministry, relatives, friends, our society people, my office to drag my father in various enquiry and cases and want to build pressure on him to pass on his property to him as per his demand and at the earliest. He has also showed me (his sister) as a greedy and manipulative person who is living with parents in greed of property. He has made up various stories which is baseless and we have all proofs to show that his information is baseless. He further drooped so low that he told everyone in written and verbal that my father has been physically abusing me since 25 yrs and therefore I stay with my parents. I am married and have 2 sons (12 and 14 yrs), my husband stays in another city due to his business there and can’t move here. I work in gurgaon and my sons study here and so we stay in Gurgaon with my parents in their flat. My brother also stays in the same flat and does not respect my parents at all. His wife also left him due to his abusive nature, he has no job since 2013 and he tried to start something on his own but failed many times. He also filed complaint in police to file FIR against me, my minor son and my father. Since Oct 2020, We have witnessed his various attacks to malign our reputation in society but my father did not take any action out of his affection for only son and also we thought that he is frustrated and he may realise his mistakes soon. As advised by family friends, My father Filed complaint under Sr citizen protection act and want his son to vacate his self owned flat. I want to know what can I do to save my reputation and protect myself and my family from his false allegations. He can go to any level to put me behind bars and spoil my social reputation. Pls help urgently