The Kid Sister (1945) Roger Pryor, Judy Clark, Constance Worth

Being the younger and prettier sister, Joan is ordered to spend the evening in her room instead of joining the party where her older, less attractive, sister is supposed to meet the neighbor’s bachelor. Unwilling to do so, she comes downstairs wearing a disguise. Not only does Joan’s plan fail, she also ends up in quite an interesting situation - sitting in the car of a burglar interested in her mother’s necklace...