Kim So Hye revealed a photo from a small I.O.I reunion on March 9.

The gathering was of the members of I.O.I born in 1999: WJSN’s Yoo Yeonjung, Weki Meki’s Choi Yoojung and Kim Doyeon, and gugudan’s Mina.

Kim So Hye just wrote in her caption, “99s.”

I.O.I, which formed after the Mnet survival audition program “Produce 101” and then disbanded early 2017, has maintained a close relationship even as the girls have joined different groups or pursued solo careers.