On September 9, Yoon San-ha updated his Instagram with a new post titled, "Happy birthday, SUA!"
The post featured photos of MOON SUA happily holding a cake, with some cream on her face, alongside Yoon San-ha.
It looked like Yoon San-ha had organized a birthday celebration for MOON SUA and spent time with her.
There were also pictures of homemade seaweed soup, a traditional Korean birthday dish, which appeared to have been made by Yoon San-ha.

Yoon San-ha seemed to be taking on the role of a big brother, making sure MOON SUA was well cared for on her birthday.
Fans emotionally reacted, saying, "Thank you for taking care of SUA, San-ha!" "MOON BIN would be happy, seeing this where he is now," "Sad but sweet," and more.

His unexpected death deeply shocked fans worldwide, leaving them heartbroken and in disbelief.
Born on January 26, 1998, MOON BIN was just 25 years old—the same age MOON SUA is now.
After MOON BIN's passing, all members of ASTRO stayed close to MOON SUA, spending time with her by going on trips, seeing plays, and doing other activities together. And now, even throwing her a mini birthday party.
Their thoughtful care for MOON SUA has touched the hearts of fans around the world.

(SBS Star)