Is it allow to sell the property?

The matter started from an injunction suit by mother in law (MIL) restraining Daughter in law (DIL in 2011) from dispossessing MIL from the shared household. Status quo was granted by Court. In same year DV was filed by DIL and residence order were given to DIL. Many appeals filed (She has produced one conveyance deed of 2010 in her favor) by MIL against the residence order but the residence order was upheld. Subsequently possession suit was filed by MIL in ADJ court asking for handing over the possession of the house. After 3 years of residence order, MIL locked the house and DIL filed application in DV for opening of house, Court ordered for handing over the keys but MIL is not doing it and appealed in session court which again ordered to hand over the keys. This time also DIL did not handed over the keys and went to HC. Now the appeal is pending in HC from 3 years. Here in DV again a fresh orders has been passed to handover the keys but DIL is again not handing over keys and appealed in HC again. Now in civil suit for possession, issue was framed (2015) that the weather MIL Is the sole owner of the property or the deceased husband was the owner (DIL has given MCD documents, ITR and other documents which shows the property is in Father in Laws Name). One application was filed 12/6 to decree the suit in MIL favor as the DIL is not residing in the house currently. The magistrate is not passing any order since 2015 on this application and delaying the matter on one or other pretext. So in nut shell matrimonial house is locked as MIL has not handed over the key and she herself is not also residing there since 2011. Keeping in view above please answer following: 1. what should the DIL do to reinstate her possession in matrimonial home. (Her application for break open the lock is also pending in DV court as the matter is pending in HC . No stay in HC is granted till date) 2. Is it possible that MIL can sell the property? if yes what can DIL do to stop her from doing so?