Born to Jewish-Canadian parents and owners of a convenience/toy/candy store called The Wiz, Lucy and Syd Charendoff, Strong was raised in Toronto, beginning her acting career once she volunteered to perform a solo in a school production at the age of four. Not long after, Strong started acting in the Yiddish Theater in Yiddish, a language she did not understand and performed phonetically. At thirteen, Strong made it into a performing arts school in which she took on her first professional role: Gracie in the Limelight Theater's production of The Music Man. Later that year, Strong booked a guest-starring role in the show T's T; following this, Strong took on the main role in Hello Kitty's Furry Tale Theater and soon after relocated to Los Angeles. She also voiced Twilight Sparkle from MLP.