SEE ALSO: DAY6 Jakarta concert marred by chaos and safety concerns

After going paragliding in Switzerland with fellow members Eunhyuk and Donghae, Leeteuk shared during a one-on-one interview with the producers, "There were also a lot of things I wanted to say right before jumping off. I was about to say things that I couldn't say before, but I didn't say any of it because I was scatterbrained [at the time]."

The mention of his family was what brought him to tears as he shared, "2014 is like a year that I want to erase from my memory... As I went up the high mountain, I thought a lot about how I'm a little closer to my father, grandmother, and grandfather who are up in the sky."

'Super Junior's Wonderful Day' will air its 4-episode marathon starting on December 31 at noon KST!