What can I do if someone is trying to damage my reputation?

I live in Australia, I have filled divorce petition first in Australia and my Ex-wife replied but she did not agree on divorce, after that she filed a false case on me and my family from Australia to an NRI cell in India which was closed on a good note after the Police did their thorough investigation. My parents are also Permanent residents like me in Australia. My ex-wife is planning to go to India now and she is doing this for a reason. She filed in Amritsar.  On the other hand, my parents had disowned my elder brother and sister in law in 2020 and his wife had filed a dowry case also in 2021.She filed in Delhi My ex-wife and my ex sister in law both are targeting us, my ex wife wants to go because she wants to support  case in my sister-in-law also my ex wife wants to take support in her case from my ex-sister-in-law. Please advise if you can advise on this matter, do you think, if my ex wife goes and meets with my ex sister in law they can hurt us more and spoil our reputation.