Actress Tang Wei expressed her affection toward IU in a heartfelt letter that she hand-wrote in Korean.

Tang Wei made her music video debut in IU's "Shh" and quickly became the talk of the town. The Chinese actress' appearance generated buzz for the already-anticipated project. The music video dropped on February 22, adding to the excitement.

Following the music video release, IU revealed that Tang Wei had written a heartfelt letter to her. After receiving the actress's permission, IU uploaded Tang Wei's handwritten letter on her social media.

In the letter, Tang Wei expressed her admiration for IU once again and wrote, "Ji Eun (IU's real name), did you know? There were two touching moments that I wanted to share with you. During the filming, the director directed me and told me the lyrics 'My eyes that are just like her mom's' that you wrote. I felt a resonance in my heart at that moment. It was something I had never thought about before."

The actress continued, "When you become a mom, moms always wonder if their child's eyes really look like theirs, but the children never really think about whether they resemble their own moms. That's why I had a strong desire to look at my mother's face in the mirror next to mine and carefully examine her face, or take a picture together and look at it for a long time. The Lunar New Year is almost here, and I'm going to meet my mom soon. So I really want to do that. I knew that you would be acting as my mom (in the music video), but it was hard to imagine even when I met you at the studio."

 Tang Wei continued to explain, "But when we began filming, you stayed in the same position on that wooden floor for a very long time, quietly and calmly holding your ground in the lighting and smoke. Amid such surreal and beautiful shooting, a scene suddenly came to my mind. The feeling that you looked like my young mother that I'd never imagined sitting next to me. My mom also had a fragile frame and a brilliant and clever look. My mother was a Chinese opera singer in her youth. In my memories, my mother's image that I imagined from my mother's old photos and from the stories my dad would tell me about her was always like an unfinished picture. My dad told me that my young mom was like a prima donna shining on the stage of a Chinese opera and a heroine receiving applause. It felt like she would be like you, who was sitting in front of me during the filming. I was really touched when I thought of that."

Tang Wei concluded the letter by saying, "Ji Eun, thank you for giving me such beautiful memories. The Lunar New Year holiday is here and I am in Beijing, far away from where you are. But I wish you happiness and health, I look forward to many more of your good songs, I am your fan. Tang Wei."

IU revealed the letters on her Instagram with the caption, "This is the letter and photos from Tang Wei Sunbaenim that she sent a little while after the filming. I was deeply moved and asked for permission from her to share the letter as well. The scene where Sunbaenim hugged me in the second half of the music video was Sunbaenim's impromptu. It was a touching moment that made tears well up in my eyes. It was a long, tense, and exciting shoot all day long. I will always like you."

Korean netizens were also touched by Tang Wei's letter and commented, "The letter is so touching," "Wow," "The letter is really touching. After I read the letter I watched the music video again and I understood what Tang Wei felt," "This is so touching," "I'm about to cry," "Tang Wei seems like a really good person," "I was always a fan of Tang Wei," "Why am I crying," and "This letter is so touching. Wow."