Jessica and her younger half-brother, Gregory, go through a lot of adventures together alongside their friends and their fairies. At times, Jessie can be quite strict to Greg, especially when it comes to his interest of pranks. Yet, Greg does know better than to act reckless and is quite protective towards his sister just as Jessie is protective to Greg. They share a lot of things together, mainly their fairies, Astronov, Neptunia and Sunny, and their own mild rivalry with Jessie against the most popular girl in school, Amanda Martin and Greg against his best friend Tommy Turner's half-brother, Otto Buxaplenty.
