My father acquired a property from his paternal uncle (no more alive) for a rs of 8000 before 30 years. For which we registered the deed on my fathers name. Now, the sellers daughter (only child alive) claims that the property was acquired by cheating from her father. With the same property my father obtained mortgage loan twice after obtaining EC from registrars office. If she files a case against our property will the case stand in court and if we can prevent her from filing such a case, what should be done prior?