The family of a young boy who suffered brain damage after enduring several unauthorized medical procedures has settled its medical-malpractice suit for $30 million.The boy’s mother — identified in court records as Ethel Chavez — sued Rush University Medical Center and physician Mark Holterman in July 2013, alleging Holterman was medically negligent when he repeatedly performed surgeries to install and replace a stent in her son’s esophagus and eventually punctured a pulmonary artery, causing him to …