Hyuk shared an Instagram post which read, "Our 'Mother's friend's son' (a Korean slang term referring to males with a friendly image) Dong Hyun, who used to come cheer me on at my movie filming set with drinks, has debuted~ Be healthy in your promotions, you body, and your heart, and let's become respectable singers together, even though this hyung also lacks. Fighting!!" 

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In Hyuk's posts, the idol sunbae proudly holds up a signed copy of MXM's 'Unmix' from his hoobae, in addition to a closer shot of the album. Kim Dong Hyun also shared the same snapshot on Brand New Boys's official Instagram, revealing that the two are from the same home town!

What a good sunbae-hoobae relationship!

????? ?????? ??????????? ??? ??? ???? ??????~ ??? ??? ????? ???? ??? ????????? ????? ??. ???!! #mxm #imtheone #??? #???????? #??? #??????????

A post shared by ??? (@hsh0705) on Sep 15, 2017 at 4:53am PDT

[#MXM/???] ?? ?? ?? ??? #?? #? ???? ??????! ??? ?? MXM ?? ??????!! #????? #?????? #??? #??? #IMTHEONE

A post shared by ?????? ?? ????? (@bnmboysofficial) on Sep 15, 2017 at 4:22am PDT