One Night, Twin Flame — Episode 10

Five years ago, Sarah of the Soo family was kicked out after falling pregnant by a stranger. Her half-sister, Lily, discovered the man was Ethan, heir to the Chou Group. Sarah gave birth to twins; Lily stole the healthy twin and married into the Chou family. Five years later, Sarah returns to save her son from congenital leukemia by conceiving another child with the father. What happens next?