Hearn was born to a relatively large family, and they lived in a small home in Grimsby, Ontario, Canada. He recalls buying the Beatles' Magical Mystery Tour and a Beach Boys greatest hits record, and having them become his first two favourite albums, which led him to an interest in performing music. He has also cited electronic band Orchestral Manoeuvres in the Dark (OMD), and folk punk group Violent Femmes, as formative influences. Hearn has a classical piano background. He attended Inglenook Community High School. He also attended St. Michael's Choir School.
