Thunder talked about older sister Dara during his guest appearance on 'Kim Chang Ryul's Old School' on December 15!

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DJ Kim Chang Ryul asked, "What was your sister Dara's response to your solo activities?" and Thunder replied, "I'm her youngest sibling.  There's a six-year age difference between us. That's why she still looks at me like I'm a baby and acts like a mother to me.  She supports me no matter what I do and tells me, 'Do your best.'"

Sibling goals!