Lee Hwi Jae�and his wife faced every parent's worst nightmare upon hearing the results of their twins' checkup on the upcoming episode of�'Superman is Back'.

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Lee Hwi Jae worried about his twins Suh Un and Suh Joon's overwhelming attachment to him and wondered if it had to do with a development disorder. He took them to take an infant development test and received shocking results by the doctor who advised that the problem had more to do with Lee Hwi Jae than the children.

After hearing the news, his wife Moon Jung Won couldn't hold back her tears with a sorry heart towards her husband and children.

Find out their story this Sunday at 4:55 PM KST.