Olivia Keville was born in Houston, Texas, to a loving, supportive family that has helped foster her passion for performing and acting aspirations. She is the youngest of three. Keville's acting career began at the age of 5, when she fell in love with the theatre after seeing a performance of Annie. She was discovered in 2016 during a workshop with Texas-based acting coach Mary Ferguson by John D'Aquino. Keville then participated in D'Aquino's young actor intensive workshop, Camp Hollywood. Her outstanding performances in the workshop's showcase caught the eye of Nikki Mincks (Mincks Talent Management), who currently represents her, along with Emily Urbani (Osbrink). On the stage, she has appeared in local musical productions, including Rizzo in Grease, Wednesday in The Addams Family, Scarecrow in The Wiz, Belle in Beauty and the Beast and the title character in Mary Poppins. Keville starred in the short film Nowhere Café and appeared in the New York Film Academy short How to Rid the House of Vampires.

Keville is also a trained singer. She has been a part of her school choir since second grade and began musical theatre at the age of 5.

In her free time, Keville enjoys writing poetry and short stories.