Her Sister's Keeper (1963)

To put her younger sister Huilan (Margaret Tu Chuan) through college, Huilian (Grace Ting Ning) became a taxi dancer and is despised by Huilan. Now married to a good husband (Guan Shan), the lonely Huilan falls for a man after her money. To protect her younger sister, Huilian puts herself at risk. Grace Ting Ning plays a sad role, as the noble sister who keeps her purity in a cesspool.