Second wife last daughter claims share in father's property

Hello Legal experts, Here are the facts of the matter of our case 1. My grandfather have 2 wives - 2nd marriage after the death of 1st wife. 1st wife with 3 sons 1 daughter. Second wife with 1 son and 4 daughters. 2. Grandfather shared property in 1982-83 in his presence, and died in 1984. Those days it was a panchayat settlement he did it without any writing. Elders who did partition are still alive. 3. 9th Daughter (Last one) have sent us a notice that she have 1/9th share in her father property. 4. She is born in 1978, got married in 1991 5. We only have a Mandal Revenue officer order copy that our property is been sub divided and all of 4 brothers have land records. 6. 1st son is died recently and we have applied for inheritance to wife and her mutation papers of 1B in AP are approved. 7. 2nd son sold his entire property within which 9th daughter husband purchased a portion of the same. 8. 3rd son died and his property is again subdivided to his 3 daughters in equal shares 9. While now when 1st son wife applying for Pattadar Passbooks in AP, the 9th daughter have put up appeal petition and RDO have called her for hearing. 10. I am the son of 4th son (second wife's son), where my father alone got all the 4 of his sisters married and took care of them until now, where the 9th daughter is behind all of us with notices, complaints in Panchat offices etc. My concern is, should we attend RDO hearing ? What kind of documents we can produce with RDO? What are the remedies available to us ? Thanks