YoonA and Sooyoung were both born in 1990, making them same-age friends within Girls' Generation.
However, the former has been speaking with the latter formally for 17 years, even calling her "unnie," a Korean honorific used by women to address a lady older than them.
During YoonA's appearance on the YouTube web show, Hyoyeon who buys us food well, MC and co-member Hyoyeon instigated the real reason their younger member refuses to use informal speech with her.
"Because Sooyoung herself is intimidating, it doesn't work, right? I should distort (the story)," teased the host.
YoonA who heard it refuted that it was the reason and started telling her story.
"From such a young age, I became friends with the unnies, and I'm good at keeping that. Even if I speak informally and act like same-age friends (with Sooyoung), it would become awkward. If I did that with the unnies, I might have to do it with everyone," explained the idol.
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"If they met me first, for example, if someone said 'Speak comfortably,' then I said, 'Okay,' I might have treated you like we are same-age friends. But I called you 'unnie' first."
As the show went on, Hyoyeon continued to get going with her YoonA and Sooyoung beefing agenda and mentioned the unofficial performance unit SNSD-S.H.Y (Sooyoung, Hyoyeon, and Yuri.
"YoonA couldn't join S.H.Y and felt a bit left out because of it. YoonA is also part of the dance line since our trainee days... Why didn't you join? We kept asking you to join us," asked Hyo.
"Maybe the unnies didn't recognize my abilities," jokingly replied YoonA.
"Was it Sooyoung who said that?" rebutted Hyoyeon, making the viewers laugh.
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