Actress Gong Seung-yeon and sister Jeongyeon discuss their bond, struggles with health, and emotional support in a heartfelt reunion.

Actress Gong Seung-yeon mentioned her sister Jeongyeon from TWICE, who suffers from Cushing's syndrome (a disease caused by excessive steroid intake). On the 20th, in the 344th episode of the tvN variety show 'You Quiz ON THE BLOCK', actress Gong Seung-yeon, who appeared in 'The Great Queen Seondeok of the 21st Century', was a guest. On this day, Jeongyeon, who was envious of Gong Seung-yeon's appearance on 'You Quiz' saying, 'TWICE hasn't appeared yet. Can you take me with you?' made a surprise appearance in a video. Jeongyeon described her sister Gong Seung-yeon as 'not normal, really scary,' revealing that when she intervened during a fight between Gong and their younger sister, she was always told, 'You stay out of it.' She also recounted an incident where she locked herself in a room after a fight, and Gong broke down the door, and another time when she tried to mediate a fight between their parents and ended up injuring one eye. Jeongyeon explained that the reason she hid one eye with her hair in TWICE's debut teaser video was due to Gong Seung-yeon's 'touch.' While Gong acknowledged many of the episodes, she seemed to disagree with the claim that she kicked Jeongyeon. She stated, 'I really hit her on the head with my hand, but she moved, so it hit her eye. I was really angry at that time. I was in the car, and I was pulled out for hitting my sister and had to walk home barefoot. It was cold, and I thought, 'I'll kill you when we get home. I won't let you go easily.' But when I saw Jeongyeon, I realized we had filming the next day, so I apologized.' Nevertheless, Gong Seung-yeon was the most reliable person for Jeongyeon during tough times. Jeongyeon shared, 'I really relied on my sister a lot. It was a mentally tough time. I don't remember much because it was so hard, but my sister caught me and said, 'You are not well. You should go to the hospital,' and took me to a big hospital, where I learned the exact diagnosis. It was the first time I heard the term Cushing's syndrome.' Jeongyeon underwent surgery for cervical disc herniation in 2020. During the treatment, she experienced side effects (Cushing's syndrome) from taking steroids, leading to rapid weight gain. She also faced panic and anxiety disorders, which caused her to halt her activities. Jeongyeon said, 'I started exercising for the first time with my sister. My sister really hates active things and is an indoor person, but she did tennis and boxing for me. She always came with me, and after her schedule, she would come, and thanks to her, my treatment went well, and I became healthy, so I was really grateful.' Furthermore, Gong Seung-yeon, who offered to live together at that time, confessed, 'At that time, Jeongyeon looked very painful. I was really anxious to leave her alone. Even when she was living in the dormitory, I kept going to the dormitory, inviting her home to do schedules or just to spend time together. I wanted her to be by my side. I was scared that my sister might disappear at any moment or give up everything.' She continued, 'I didn't know what that mental state was like, what kind of pain she was experiencing, or what was hard for her, so I tried various things. When my sister said bad words, I tried hitting her, getting angry and saying, 'Get a grip,' calming her down, and crying together. Still, just being there silently was the best for her at that time. I just stayed by her side. When it was time, I prepared meals for her.' Yoo Jae-suk remarked, 'Chan-hyuk from AKMU also said he wanted to exercise together for Su-hyun. It seems that family becomes a great support during such times when people who lived separately say, 'Let's live together.' Jeongyeon sent a video message to Gong Seung-yeon, saying, 'I'm really happy that you have been in the spotlight recently and succeeded, and I'm grateful that you are my real sister.' As she spoke, Jeongyeon shed tears, saying, 'I'm sorry for making you go through hard times without knowing or realizing it. I'm really sorry. My sister and I had a long trainee period, so we went through many ups and downs. Now we are both on the right path, and I am really grateful. Let's live healthily, we really love each other.' In response, Gong Seung-yeon, who also showed tears, said, 'We've had a lot of things happen until now. Thank you for getting healthy and overcoming it. I said I wanted to be your sister in the next life, but no, I want to be born as your sister in the next life.' She joked, 'I really love you too, and let's always be the best friends,' showing the bond between the sisters.