File a suit for defamation under IPC. For any further information, feel free to contact me on my e-mail "firstname.lastname@example.org"
Advocate Shubham Pabbi
It is pretty simple. You can issue a cease and desist notice on those relatives to ask them to stop defaming you further and if they were to, then they would be taken legal actions against. Most often than not, after this the other party don't indulge in the fear of legal proceedings.
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