Property dispute case

My father got an house in 1986. Till now, we have been residing in the same house for more than thirty years. My father got this for Rupees 3500. The sold person died. But his wife filed a case in 1990. Then her son in law continued the case. My father is illiterate that he doesn't have most of the documents. The case was forwaded to Madurai high court. Then it has been pending in lalgudi subordinate court in Trichirappalli. My father met an road accident three years before and he is unable to be normal. I just come to know these things and got the broad picture about the case just before.Recently the lawyer of our case stated the case may move in favour of opposite party and within ten days, the court may ask us to vacate our house. My question is....as we reside for more than 30 years, We know that the case is falsely fabricated for the motive of making money alone. Since we don't have much documents to substantiate and the land is near to a river side, in that area none has received the Patta so far, Can we have our justice?