Super Junior's Yesung talked about being mistaken for being the son of former North Korean leader Kim Jong Il on 'Strong Heart'.

Back in 2009, Swiss and German newspapers had run articles with pictures of the Super Junior member depicted as Kim Jong Il's son, Kim Jong Un. Boom introduced the topic by saying, "This story was shushed and avoided by everyone. There were rumors of Yesung being Chairman Kim Jong Il's third son. It was written on German and Swiss newspapers."

Yesung said, "My real name is Kim Jong Woon. Because our names are similar and my pictures are all over the internet, I think the foreign newspapers misused my picture. The picture they used is actually a photo from our first single jacket."

MC Shin Dong Yup asked, "What does your father do?" and Yesung answered, "He owns an eyewear store in Myung Dong."