Serenity Wheeler, known as Shizuka Kawai in the Japanese version and Shizuka Jonouchi in the Toei anime, is Joey Wheeler's younger sister.
The two were separated at a very young age when their parents got divorced. In both series of the anime and the manga, Serenity is depicted as being a sweet natured, gentle, fragile and dependent young girl.
She has a small fragile body, flowing auburn (brown/red) hair, and gentle dull greenish brown eyes. Throughout the whole series she is pictured as gentle but strong, with a never changing attitude of high spirits.
She's the love interest of Duke Devlin and Tristan Taylor.