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During the March 17 episode of 'Knowing Brothers', Wheesung and Kang Han Na made their guest appearance on the show where they revealed some unknown facts and experiences about themselves.�

Wheesung confessed during the Q&A session that,�back in the day, he used to text himself whenever he felt extremely lonely. He explained, "In the past, the person sending the text messages were able to modify the phone number. For example, I would save the number 486 under Han Na and send myself a message, 'Oppa, what are you up to?' then turn back around to look at the message."

Hearing this, Heechul joked, "I did hear this hyung�isn't sane. His character�overlaps with mine way too much, I'm uncomfortable." Seo Jang Hoon also added, "We understand it...but that's pretty serious." Wheesung answered back, "Well, I was seriously lonely back then."