TS Entertainment confirmed the sister group of Secret, SONAMOO.

In Korean, "sonamoo" means evergreen tree. The meaning of the group's name is to stay the same as the evergreen tree does and perform lively music.

TS Entertainment revealed their third member, Euijin. Before, they revealed the members New Sun and Nahyun.

The members are still in their 10s and have great talent for singing, acting, and rap.

TS Entertainment stated, "There are many things that we have not revealed yet. We are going to support them to make their debut a hit."