From Girls' Generation's Yuna & TIFFANY to Seohyun, celebrating their 17th debut anniversary... ”Congratulations!” in casual and mixed phrases

The members of the group Girls' Generation celebrated their 17th debut anniversary. Yuna released her first album, Girls' Generation 17th Debut on the 5th.
Tiffany said "Seventeen," and YURI said, "Congratulations on your 17th anniversary."
Suyeong said, "Fany, Soshi, and Sowon Happy
Birthday. Starting today, Seohyun will talk to his sisters in a casual manner.
Seung-gyu, I miss you." Seohyun replied, "Happy 17th birthday Girls' Generation (roughly synthesized, please understand.
Seung-Gyu, our hearts are always the same," he said, "GGFOREVER. That's right.
"I'm the one who decided to talk to you in a casual manner, haha," Hyo Yeon added, "Happy 17th anniversary Girls' Generation," and added, "Thank you Sone for always being with us."
They appear to have come together to celebrate the 17th anniversary of Girls' Generation's debut. Their unchanged beauty shines through. Sunny, who couldn't join in, was added in via photoshop, drawing laughter.
In particular, Seohyun drew an enthusiastic response from fans when he said he decided to speak in casual language.