Is it legal for my fathers girlfriend to deny an autopsy for him in North Carolina. Should the hospital have called my siblings and I to let us know.

My dad died at home. He went to sleep and did not wake up. By the time we called the hospital about an autopsy they said his wife and mother called and did not want one done. He was not married and the other lady was his step mother. His mother did not know at that point he had passed. We wanted an autopsy and no one asked my siblings and I or notified us of anything until my mother called the hospital and they told her the funeral home was coming to get him because of the girlfriend and step mother lying.