Steph! <3 She's from CSJH and in Japan, they're known as Tenjochiki (if I spelled that correctly).
ChaeYeon is like Lee Hyori's age. She doesn't have any talent in particular (or at least I think so) in her voice. But she is a VERY cute and pretty girl, easy personality which tv entertainment loves. So she's famous and she's had a few rumors with famous (HOT) male Korean stars as couples. She's on and off in the spotlight. As of right now, it's off.
-O_sLaVe