Both have a delusional sister in law and I do find some other similarities like the second lead female blaming everyone except herself....

Kind of the same plot. .. "Yoon Joon-suh and Yoon Eun-suh grew up as siblings but Eun-suh was in fact from a different family as there was a mix up at the hospital where she was born. The switch came to light when Eun-suh was involved in a car accident and it was discovered that her blood type was different from her parents. Eun-suh's life took a complete turn when the 2 girls were returned to their respectivefamilies. Soon after, the Yoon family left for the States and Eun-suh was left living in sordid condition with her real family in Korea. Years after, Joon-suh returned to Korea and by chance the two former siblings were reunited."