How to protect our right in suit lands

How to protect our rights in suit lands My paternal grandfather (GF) and his 2 brothers were divided their ancestral properties in the year 1930 and executed unregistered partition lists, from then they living independently, after some time it was impounded with sub-collectors office. After some time they lost impounded partition lists and again they executed registered partition deed in the year 1952 in it they stated for the evidence of their children in future the partitioned was affected in 1930. Before partition my GF’s elder brother purchased house property in the year 1923 and mentioned his self-acquired in the joint family partition deeds in the year 1930 and 1952. After joint family partition in 1930 my GF independently purchased with his own funds, 20 lands different survey numbers and some house properties at civil court open auction in the year 1933 which includes entire suit land. My GF alone sold most of the properties before 1972 which purchased in 1933. My GF’s elder brother (Donor) executed registered GIFT DEED without any right, title, possession and enjoyment in the year 1984 in favour of his daughter and son-in-law conveying 1/3 share in only 2 survey numbers by stating it is joint family property but his younger brother not claimed any lands purchased in 1933 by my GF. The Suit lands not at all mentioned in the registered partition deed executed by donor and his sons in the year 1953 and in it also mentioned that 3 brothers were partitioned in 1930, the same he was admitted in the file of AP Land Reforms declaration in 1975 and he (Donor) has not claimed suit property in his said declaration. After demise of my GF all his legal heirs were divided and executed registered partition deed in 1987 which includes suit lands and other properties. The suit lands in the name of my GF and his family in all the revenue records since from 1933 in our possession and enjoyment, done or donor never in possession at any time. The suit lands mortgaged in favour of co-operative bank by my father and GF obtained loans by way of registered mortgage deed in the year 1960. In 2003 the done filed suit against my father and my aunts in civil court for declaration for right, title and division. Q1. Kindly tell us merits and de-merits of the suit to protect our rights in suit lands. Q2. Kindly refer Andhra HC and Supreme Court related judgments to suit. REGARDS