My late wife did not get along with her father and rarely saw him in the last years of his life.

His will left his estate equally to his daughters, one of whom was given power of attorney. His home was transferred into her name to protect it in the event of a prolonged illness. It, along with antiques in the home, were his largest assets (total value of the real estate and antiques was about 150k). There was a small amount of cash (70-80k).

After his death the daughter who was executor never probated the will and maintains that there were no assets.

A number of times during the last years of his life, her father expressed to me personally that he intended for both daughters to share and share alike in his estate. Is there anything that can be done to address this matter? My son, as executor of his mother's estate is wondering how to proceed against his grandfather's estate and/or executor on behalf of his mother's estate.