Bang Hyun Ah appeared as the 4th mystery singer and introduced herself as Minah's sister. The debate on whether or not she's a truly�talented singer and the sister of Minah heated up among the panelists.�

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To reveal her identity, Bang Hyun Ah performed Girl's Day's ''Something''. As soon as she sang, Bang Hyun Ah shocked everyone and proved to be a talented singer, as well as Minah's older sister.�

Minah also made a surprise appearance despite her busy schedule�and showed support for her sister�

It's also turned out that Bang Hyun Ah actually made her debut in the girl group Wanna.B�in 2016.�

Minah shared a comment, and said, "I wanted to be supportive but I wasn't able to provide encouraging words. I still don't know how to express it so that's why I decided to make an appearance like this. I hope my unnie�succeeds. As a dongsaeng, I'll be supporting her."