In a state of limited or lacking legal capacity, however, the question quickly arises as to who can act for us, who can make declarations and who should make decisions.
If the person concerned has not taken any precautions, the state will appoint an official guardian in court. This person takes over all decisions and representation rights. The family members then have no rights.
You should therefore appoint a person you trust as your representative and determine precisely the content of his or her duties and the scope of his or her powers.