One Night, Twin Flame

Five years ago, the Soo family's young lady, Sarah, was kicked out of the family after she was impregnated by a mysterious man. Her half-sister, Lily, found out that it was Ethan, the heir of the Chou Group. After Sarah gave birth to twins, Lily stole the healthy of the two, which was the elder twin. Then she successfully married into the Chou family. Five years later, Sarah came back to cure her son who had congenital leukemia by having another child with the father. How will things turn out?