The Major and the Minor

The Major and the Minor is a 1942 American comedy film starring Ginger Rogers and Ray Milland. It was the first American film directed by Billy Wilder, and launched his incomparable directing career. The screenplay by Wilder and Charles Brackett is based on the play Connie Goes Home by Edward Childs Carpenter.

When the train is detained by flooding on the tracks, Philips fiance Pamela Hill Rita Johnson and her father, his commanding officer at the military academy where he teaches, drive to meet him. Pamela boards the train and finds SuSu sleeping in the lower berth in his compartment. Imagining the worst, she accuses Philip of being unfaithful and reports his alleged infidelity to her father. Indignant, and still feeling protective of SuSu, Philip insists on bringing her to the school where her parents can retrieve her. The Hills, meeting SuSu in person and now believing that she is onlyyears old, agree to let her stay with them.Pamelas teenaged sister Lucy Diana Lynn immediately sees through Susans disguise. She promises to keep her secret if Susan will help her sabotage Pamelas efforts to keep Philip at the academy instead of allowing him to fulfill his wish to be assigned to active duty. Pretending to be Pamela, Susan calls one of Pamelas Washington, D.C. connections and arranges to have Philips status changed. ........

Source: Wikipedia