K-pop idols VIVIZ SinB, SEVENTEEN Seungkwan, and iKON Chanwoo have taken to Instagram to share their grief over the loss of their close friend, ASTRO Moonbin. The four artists, known as the "98 liners," were born in the same year and had maintained a strong friendship for over 18 years.

As the music industry mourns Moonbin's passing, fans have been particularly concerned for the 98-liners group, as they were known to be closest to the late idol.

On April 21, VIVIZ SinB paid tribute to Moonbin by following his personal Instagram account. She had previously only followed her former GFriend members, and the addition of Moonbin's account is a poignant reminder of their connection. SinB and Moonbin were not only born in the same year but had known each other since they were eight years old, as they both grew up in Cheongju, North Chungcheong Province. Their friendship continued through their careers, with fans admiring their genuine bond.

SEVENTEEN's Boo Seungkwan, another of Moonbin's best friends, also expressed his sorrow by visiting and following the late idol's Instagram account. The two were members of the '98-liners squad and were open about their close friendship in various interviews and broadcasts. In a previous interview, Moonbin had expressed gratitude for Seungkwan, who enabled him to enjoy going out and experiencing new things.

iKON's Chanwoo joined SinB and Seungkwan in mourning Moonbin's death by sharing a heartfelt message in an Instagram story. He wrote, "Bin-ah, don't get sick there and stay happy." Along with the message, Chanwoo posted a childhood photo of himself with Moonbin, recalling their shared experiences as child actors and the friendship between their parents.

In 2006, both Moonbin and Chanwoo appeared in TVXQ's "Balloon" music video, with Moonbin as "Little Yunho" and Chanwoo as "mini Changmin." They also appeared together in the 2009 KBS2 drama "Boys Over Flowers," with Moonbin playing the child version of actor Kim Bum and Jung Chanwoo portraying the child role of actor Lee Minho.

As the industry and fans continue to grieve ASTRO Moonbin's passing, the outpouring of support and tributes from his closest friends offer a touching insight into the late idol's impact on their lives.