My father is dying in hospice. My younger brother who is a real SOB has managed to manipulate his name on my fathers will.

My other brother and I are concerned this creep is stealing from the estate and whatever is in the will for us will be gone when my father dies. What can I do if he's stealing money and or refuses to give me a copy of the will? My father told me I'm in the will as a beneficiary. Thank you for your help