Mortgaging a disputed property

My father wrote a settlement of an ancestral property( a gift from his maternal grandmother) on my younger sibling's name who was a minor till 2017. After 1 year of writing the settlement, he went on to cancel it (without court's permission) and transferred the property to his name again. After a couple of years, he separated from my mother, with me and my brother under complete care of her. After consultation with lawyers, she came to know that the cancellation of settlement does not hold under constitutional law and hence filed a case against him in the court. While the case has been going on for a few years now, he (my father) has recently mortgaged the same property for xx lakhs in the bank without the consent of my brother (who is now a major). Can we file a case against him in court for mortgaging a property that was already under legal disputes and misusing, defrauding my brother as well as the bank under the pretense of which he claimed the property to be in his name to avail the loan?