Jisook (지숙; born Kim Jisook (김지숙) on July 18, 1990) is the main vocalist in the group.[28] She studied at Hanyang Women's University, majoring in music. She is known for resembling Girls' Generation's Kim Tae-yeon.[34] Before Rainbow, Jisook was in a pre-debut rock band. Her mother died of chronic disease on July 4, 2011, during promotions for "Sweet Dream".[35] Jisook is also a member of the group's sub-unit Rainbow Pixie.