The assets are taken over by one sibling, Mother died without will

My father left a detailed registered will in which all assets went to my mother and after her he divided it among his 4 daughters. After his death mom got the main house transmuted in her name but she died a year later without any will. Youngest daughter was to execute the father's will and also was trusted by mother to do the needful. However the youngest has transferred all deposits and securities in her account, and she is occupying two of the three flats left in the main house. Not sharing the death certificates of parents or disclosing the assets. Have invited her a number of times but she says no money is left. My research through information known to me talks of movable assets worth 2 cr. What should I do. The other two sisters are just waiting for something to happen. Can I file a succession suit independently to access my 25% share. I have a legal heir certificate of 4 of us for both parents.