My Forbidden Past (1951)

Barbara Beaurevel lives with her aunt and cousin in New Orleans in the late 1800s. She's in love with Mark Lucas, a research doctor at Tulane University, but her plans to marry him are thwarted. Her family is of the high-society stratum, but her late grandmother was not, and the connection with her is something that Barbara's aunt is most anxious to conceal. After Barbara inherits a fortune from her grandmother's side of the family, she uses it to try to win back Mark.