Elizabeth was born in Shrewsbury, New Jersey, and grew up in the Jacksonville, Florida area from the time she was a young child. She is the daughter of David and Christine Posey, and cousin to actor Tyler Posey. Her father is brother to actor John Posey. Her heritage is Irish, English, and Swiss. Elizabeth developed an early interest in the arts and began her acting career performing on stage throughout her adolescent and young adult life. She attended the University of Florida in Gainesville, Florida where she duel majored in Public Relations and Theater. After graduation, Elizabeth moved to Los Angeles to pursue her acting career. Elizabeth is also classically trained in voice, and has studied music from the time she was 7 years old.