Child actress Kim So Hyun sang "First Love" for her drama 'Suspicious Housekeeper'! The song is a sweet modern rock song. It puts Kim So Hyun's clean voice with a warm acoustic guitar and an easy melody. It shows Kim So Hyun's girlish emotions perfectly. The child actress plays Eun Sang Chul's (Lee Sung Jae) eldest daughter Eun Han Gyul. Han Gyul learns of the secret surrounding her mother's death and butts heads with her father, but she also maintains her composure as the unshakable daughter who plays a role in bringing the family together.