Will disputes

We are 3 daughters to our father. Our mother demised on 12.03.2003 due to sugar and other ailments. After our mother demised our father got married again one Mrs. Agnes from Kerala on 11.07.2004. But no children to her. Unfortunately our father died on 08-11-2014 during harness. We are the legal heirs of our father. Sir/Madam, we would like to bring to your kind notice that we had disputes with the second wife of our father. Regarding the disputes, we have approached the honorable court dated on 05-02-2015 and the suit no is O.S.NO:22/2015 which is pending adjudication. Now she is claiming our father’s property that she got the unregistered will, but the will got certified by the local notary. We are 200% sure that that will is forgery one. Kindly advice us that how to prove that will is forgery one. The case is going on more than 9 months. Still she didn’t produce the will, in the court. But the same time she is trying sell the property based on will. We would like know that whether she can sell the property? How to stop it?