Red Velvet's Irene, Wendy, Seulgi, and Joy were on TV Chosun's 'Idol Party'. The girls talked about their back stories, and Seulgi, who had the longest trainee period, said, "During the 4th or 5th year of my trainee period, I had a big slump. I barely just hung on because my mother cheered me on saying I'd definitely do well. Later, I found out that my mother also had hard times during that time." 

She teared up thinking about her mother and expressed her sorry as well as gratitude. The other girls also talked about their trainee period and everyone ended up reminiscing and tearing up.

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The show 'Idol Party' is MCed by Kim Joon Ho, Leeteuk, and Solbin. The episode will air on the 26th.