What should I do ifa family member dies and suspect thata hospital, doctor or nurse was negligent or committed medical malpracticein causing the wrongful death?

You must immediately request an autopsy so that the cause of death can be established.  If an autopsy is not performed at or near the time of death, valuable evidence of the cause or causes of death could be lost and it will make it very difficult to overcome the alleged cause of death which is placed on the death certificate.