Hello Chalky.1,
In the USA, a doctor will talk to/inform/discuss an adult patient's case with a family member only with the written consent of the patient. This consent is kept on file. Also, I have a copy that I can carry with me. My 19 y-o son signed a form called, "An Advanced Directive" stating that I am his assigned "Agent"

In this form, my son stated that besides himself; I too can make decisions as they apply to his care.