The member who was added to Red Velvet after their official debut was Yeri. She joined the group in March 2015, making her debut with them in their first studio album, "The Red", which was released in September 2015. Yeri was only 16 years old when she joined Red Velvet, making her the youngest member of the group. Despite joining the group after their debut, Yeri quickly adapted to the group's concept and became an important member of the group, known for her cheerful personality and powerful vocals.