Most viewers have come to love the families on 'Superman is Back' as if they were their own, and although a sense of kinship was formed through the broadcast, not many know what the children and 'supermen' are like offscreen. The show's PD Kang Bong Kyu�revealed what many are curious about in an interview.

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The PD talked about the father of the 'choovely' family, Choo Sung Hoon,�"As a Judo and martial arts athlete, I think Choo Sung Hoon wants to show the image of a 'strong man'... He acts cold around [his wife]�Yano Shiho�when the cameras are rolling, but he is really affectionate in person... Once the producers say that filming is over, Choo Sung Hoon lets loose and shows a natural image."

The PD also revealed that Lee Hwi Jae was the most hesitant to join the show because it would mean letting the public into his private life. At the time of the show's pilot, Lee Hwi Jae said,�"I'll do it for only one year."�The PD stated, "Since he hasn't said anything yet, it seems like he will continue to do it... I am thankful as a producer... I joked to Lee Hwi Jae that we should do it until the kids start going to school... Although it's my personal wish, if that were to happen, I want to create a special documentary on the children's growth."

He also commented on Song Il Kook�and his triplets,�"Song Il Kook is a really gentle father and husband. When we're filming in his home, he's sensitive [to others' feelings] to the point that it feels like the roles of the man and woman have switched... As we watch how he interacts with�Dae Han, Min Guk, and�Man Se, [we see that] he really is an affectionate guy."

The PD shared how the children are growing up so fast and said,�"The children look different every time we see them. Whether their faces have grown sideways or vertically, there are a lot of changes. It's to the point that we can't believe it's the same child. As they grow up, they are all getting prettier."