Knowingly Unknown(모르는 사이)

Kyung-hye is having a minor friction with her daughter Ye-shin, who is going through puberty every day by day. Moreover, both Ye-shin and Kyung-hye are on edge because Ye-shin seems to have a boyfriend. But one day, Kyung-hye sees Ye-shin and her best friend Su-jeong kissing in front of her house.