My husband's father died last year and his brother refuses to let him or anyone else see the will. Is it possible for my husband to see it?

My father in law wanted all of his assets and possessions split between his two children equally. This didn't happen. My husband's brother wrote the will himself and will not share what it says with anyone else. He's the only person who knows what it says. He also forged their father's signature. He has kept everything their father had and made himself the will's executor. It seems fraudulent and morally wrong. My husband is heartbroken because his father's wishes were not done. He would like to get to the bottom of this for his father's sake and for his own piece of mind. He feels it to be disgusting and terribly wrong because in his mind he feels like his father's death is not being honored. Is there anything that he can do to ease his pain due to the extreme disrespect for his father by the wrong doings of his brother? Could he be allowed to see will at all? He's never been in this situation and I haven't either so we are clueless about the possible things that can be done about thi