It was an emotional episode on the October 14 airing of On Style's 'THE TaeTiSeo'.

At one point, Heechul was giving Taeyeon advice, which moved her to tears.  He said, "Don't look at the internet and don't listen to people whose faces you don't know.  People whom you can see like this put their name on the line when they talk to you.  However, other people..." and pretended to be typing on the computer, making people laugh.  He continued, "Don't be in pain.  Anymore," and gently stroked Taeyeon's hair.  

Taeyeon told him, "Thank you for coming," to which he replied, "In our relationship, let's not say thanks or sorry."

Taeyeon also showed her gratitude towards Tiffany.  The production crew was preparing a secret video for Tiffany, so they asked Taeyeon what she was grateful for in regards to her groupmate.  

She said, "There were a lot of times I was thankful.  When I was home for over a week, she came and dragged me out, saying I was going to get depressed like that.  She lets me get some fresh air.  She's someone who can change my moods."

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In addition, this was their last episode of 'THE TaeTiSeo,' so they were asked the same question from the production crew they were asked at the very beginning of the show: "Are you happy?"

While they were unable to readily answer the question previously, the members now all said, "We're happy."

Taeyeon said, "I earnestly thought about happiness.  However, I was able to find it nearby rather than from somewhere far away."  Seeing this, Tiffany said with surprise, "Taeyeon has changed."

The three then shed tears as they received presents from the production crew.  Tiffany said in thanks, "What I prayed for while promoting as TaeTiSeo was to meet people who would trust us and view us preciously."