On February 9, Segok Middle School in Gangnam, Seoul held its graduation ceremony. Among the graduating students was Seo Yeon, a.k.a TWICE Jihyo's youngest sister. 

The whole family including the idol star attended the event together. 

It's reported the unexpected appearance of a popular girl group member made everyone overly excited and turned the day even more special for the graduating students. Jihyo also took the time to take photos with her sister's friends and other fans. 

This year's graduation will definitely be an unforgettable memory for students and families of Segok Middle School!