Krystal is a Korean American singer, actress and the youngest member of the five girl idol group, F(x).
Discovered by S.M. Entertainment in 2000, she began filming for commercials and music videos by 2002. During a family trip to South Korea in early 2000, at the age of five, she and her older sister Jessica Jung were spotted by talent agency S.M. Entertainment, which earned her a cameo appearance in Shinhwa's "Wedding March" music video. The agency saw potential in both Krystal and her sister and offered them singing and dancing lessons, opting to professionally train them in a singing career. However, the offer was turned down by her parents, reasoning that Krystal was too young. Therefore, her parents at first only allowed her older sister to join the agency, who debuted as a member of the girl group Girls' Generation. Since then, the Jung sisters have appeared together in many events.
In 2002, Krystal began appearing in television commercials. She first appeared in a Lotte commercial with South Korean actress Han Ga In. In 2006, her parents finally allowed her to join S.M. Entertainment, and the agency then enrolled her in dance classes, including jazz and ballet. Krystal was trained for 3 years before debuting as a part of f(x) in 2009.