A guardian is a court-appointed individual who is authorized to make personal and medical decisions for someone who is no longer able to make such decisions for him or herself.  A guardianship is also necessary when a disabled child who is not capable of making all or some of her decisions reaches age 18.  A family member may request to be appointed, or a nursing home or other health care provider may ask that someone, often an attorney, be named to make these decisions for an incapacitated person.  Usually, if a person has named a valid health care proxy, a guardianship proceeding is not necessary.