Kim Seong-joo revealed that he underwent gallbladder removal surgery while appearing on 'Miss Trot 4.'

On the April 2 broadcast of TV Chosun's 'Miss Trot 4 Talk Concert,' Kim Seong-joo disclosed that he had surgery due to health issues. He explained, "I had my gallbladder removed," adding that his condition was poor at the time, making the surgery necessary. Kim Seong-joo mentioned a period after the surgery when he was deeply concerned about work, saying, "I wondered if it was worth working to the point of harming my body, and when I thought 'what if,' tears just kept flowing. It was a touching moment."

During the broadcast, Jang Yoon-jung referred to the superstition that when Kim Seong-joo cries, the person will succeed, and asked who the most memorable contestant was. In response, Kim Seong-joo said he first shed tears during Lim Young Woong's performance of 'The Story of a Certain Elderly Couple in Their 60s.' He added that he was emotionally overwhelmed during Jeok-woo's performance of 'Everyone' because he was about to undergo surgery due to health issues. Kim Seong-joo said, "Songs sound different to each person. To some, they sound joyful; to others, sad. That happened. So, 'Miss Trot 4' will remain a memorable experience for me."