Kammala jumla mai zuwa: Knowlden ya yi aiki a cikin fina-finai, da yawa masu yawan kuɗi, a cikin shekarun 1930. Sau da yawa ana jefa ta a matsayin 'yar manyan haruffa, ko a matsayin babbar mace a lokacin ƙuruciyarta. Da yake kama da wani matashi na actress jefa a matsayin manyan lady ne sau da yawa wani babban dalilin da ya sa ta aka jefa a wani rawar. Ba kamar yawancin 'yan wasan kwaikwayo ba, yara da manya, a lokacin zamanin tsarin studio, ba a taɓa yin kwangila da wani ɗakin karatu ba. Baya ga wani lokaci na wucin gadi a lokacin yin fim din "Marie Antoinette" lokacin da ta yi karatu a Metro-Goldwyn-Mayer's Little Red Schoolhouse, ta tafi makarantar jama'a maimakon makarantun 'yan wasan yara a Hollywood. Ta kasance a cikin Greta Garbo da Clark Gable's 1931 fim "Susan Lenox (Her Fall and Rise) " amma an share al'amuran ta a cikin yanke na ƙarshe. A shekara ta 1933, Knowlden tana da rawar da ba a san ta ba a matsayin yarinyar Flora a cikin wasan kwaikwayo na pre-code "Little Women", wanda Katharine Hepburn ya fito, kuma an ba shi lambar yabo ta Academy Award don Mafi Kyawun Hotuna a
Kyautar Kwalejin Kwalejin ta 6 a 1934.