What to do my aunt is facing a property dispute

My aunt is having property dispute with one of her relative. Previously she had taken education loan against the property (her own house as a mortgage). But after some time she was unable to repay it due to personal problems. Her relative came to rescue and said I will deposit ur EMI and later u can give me ur house. Aunt agreed. ( there was no formal agreement on this, as it was house matter so it was quite informal).. After paying some EMI one day he said we should have an agreement on paper.. And took thumb impression on paper of my Aunt and her son and daughter. And after a while he stopped giving EMI. Now few days back he said give me all my money. Aunty said I don't have money as this is very big amount. He filled a case. Police has registered a case under IPC 420, 120 AND 34. Important point is my aunt is suffering from kidney problem also. She is doing dialysis on her own regularly. Now please suggest what should she do in order to solve this case.