It's a known fact that Yoo In Na and IU are besties. And hawk-eye netizens are at it again, as they suspect Yoo In Na knew about IU's relationship with Kiha & The Faces member Chang Kiha since the beginning.

An online community post titled 'Yoo In Na knew the truth about IU and Chang Kiha's relationship' is gaining a lot of attention. The post features a radio broadcast of 'Yoo In Na's Volume Up' from back in January 27, 2014 where IU was a guest.

At around the 28:40 mark (see video below), when a listener requested Kiha & The Faces "Living the Carefree Life", Yoo In Na asked IU out of nowhere, "I have a wish. I wish you would sing and introduce this song."

IU typically did what Yoo In Na asked of her, but this time around, she seemed flustered as she declined, "Why? It's too hard."

Yoo In Na kept going, "Just cause. You're a good singer."

Many of the comments on the community post agreed that Yoo In Na definitely knew about IU's relationship, and that the request seemed out of nowhere.

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Watch the radio broadcast at the 28:40 mark to decide for yourselves! Do you think Yoo In Na knew and 'teased' IU a little bit on the show about her then-secret relationship?