After School's Kaeun turned red after making a mistake on '1000 Songs Challenge.'

During the recent episode, Kaeun's voice broke while singing a high note from Uhm Jung Hwa's "Festival," making the other guests erupt in laughter.

After the song ended, MC Lee Hwi Jae, who had expressed his love for After School earlier, teased her by saying, "I really liked you, but I'm disappointed. I thought you were singing trot" and imitated her voice breaking. Kaeun looked flustered as she explained, "It's because I was nervous."

Meanwhile, MC Jang Yoon Jung also teased Lee Hwi Jae as she told him, "You take care of Kaeun too much. You always say 'our Kaeun.'" And Lee Hwi Jae replied to her, "I'm taking care of Kaeun because her last name is Lee."

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