Seong Ri and Kyeong Bin are twins born via artificial insemination, later separated at birth. Both twins are unaware of each other until Seung Ri's mother abandons her one day and forces her to go to her real father. Seung Ri misses her mother and has difficulty in adjusting to her new family, including her twin brother and 3 sisters. Her friend's brother Soo Cheol befriends her eldest half sister who is able to hear but unable to speak due to an accident during childhood.