Lee Songhyun

On September 15, 2021, she was announced as a contestant on the singing survival show Kookmin Singer. Songhyun participated in JYP Entertainment and KBS2 survival show The Entertainer, where she ranked 4th, thus earning a place in the girl group DDDD 25. It is presumed that DDDD 25 has disbanded without debut sometime in late 2025.

On January 9, 2026, Lee Songhyun was teased to be part of an upcoming project. On January 13, INNIT Entertainment revealed she is a member of the duo dodree and they would be debuting with their first digital single "Just Like A Dream" on January 21.