boy wonder
From Longman Dictionary of Contemporary Englishboy wonderˌboy ˈwonder noun [countable] SUCCESSFULa young man who is very successful Robson, the boy wonder of the departmentExamples from the Corpusboy wonder• At age 27, Williams was the boy wonder of banking.• The boy wonder is 43 now.• Once more in conflict with Stroheim, the young boy wonder of Metro had Stroheim replaced and the film drastically cut.