    Sentence 1: Adolescent specialist  Dr Michael Cohen , who worked on  the study , said doctors had  treated eight-year-old children  with anorexia - and that he had  once treated a four-year-old boy .    Sentence 2: Adolescent specialist  Dr. Michael Cohen , who worked on  the study , said doctors had  treated 8-year-old children with  anorexia _ and that he had once  treated a 4-year-old boy .