MBLAQ's Mir admitted that his sister is his biggest rival.

On the episode of SBS 'Strong Heart' that aired on January 24th, Mir remarked, "My sister and I have a good relationship but we are envious of one another," surprising everyone on set.

"When my sister found out that MBLAQ earned a #1, she was really bitter," he continued. "Instead of congratulating me, she sighed."

"But to be honest, when I heard my sister was starting a new project, I caught myself sighing as well," he admitted, causing everyone on set to explode in laughter.

Also on the episode, Seo Jun Young remarked, "I was more popular back in school than I am now."

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Source & Image: XportsNews via Nate