YoonA was a surprise guest on the November 6th episode of 'Strong Heart'.

YoonA presented Leeteuk with a Girls' Generation signed CD and gave him a hug, saying, "He was a leader that led not only Super Junior but the entire company. I'm worried about who's going to take over his place."

She added, "I'll go visit him in the army if my schedule permits. I hope the album helps him. Be strong in the army."

The MCs of the show said, "When you go there, the Girls' Generation CD will be your weapon", and Boom added, "If you give it to your superiors, they'll go insane."