Her maternal grandfather was former congressman Ron Dellums; she and her mother were able to connect with him a year before he died.
[3] Pfeiffer graduated from University of Michigan with a BFA and attended the Royal Academy of Dramatic Art in London.
[5] Pfeiffer began her interest in music by taking violin lessons at four years old.
[3] She attended theater camps and performed in her middle and high school productions.
[3] In 2016, at 21 years old, Pfeiffer was selected by Gustavo Dudamel to perform as Maria in West Side Story at the Hollywood Bowl after the Los Angeles Philharmonic's artistic team showed him YouTube videos of her performing.