Born in Waco Texas in 1979, both of Jennifer's parents were in the medical industry. Her father Herbert Hewitt was a medical technician, and her mother Patricia Mae was a speech-language pathologist.

Her parents divorced when she was young, and Jennifer's mother raised she and her brother Todd on her own.

Jennifer has always loved music, and she sang and danced at an early age. When she was ten years old, she moved to LA with her mother to pursue a career in acting and music.

Early on, she appeared in commercials, than starred in Kids Incorporated on the Disney Channel. Her breakout role was in Party of Five. She currently stars in the Ghost Whisperer. In 2001, Jennifer made $4 Million US dollars for her roll in Heartbreakers.