McKenzie was adopted as a newborn and raised in Cave Creek, Arizona. The oldest of three children, she's described as creative, free-spirited and the pack leader. An antique piano sat in the living room of her childhood house; she was engrossed in the sound of delicate notes filling the room as her mother played songs she learned throughout her youth. In that moment, music became McKenzie's biggest fascination. ​ One of her earliest memories is crawling up to the piano bench, nervous to press a key as not to create too much noise. Note by note, McKenzie's confidence in her own abilities continued to grow as she taught herself simple chords. After hearing her daughter's enthusiasm and ability to play piano by ear, her mother enrolled McKenzie in piano lessons through her homeschool years until starting her 7th grade year at a charter school.   ​As she sat before a mirror and discovering her voice, singing her favorite songs (including "Ready to Run" by the [formerly] Dixie Chicks) and creating her own simple compositions, melodies and lyrics, close friends and family members witnessed as McKenzie quickly spiraled into a music and performance obsession. Like so many young children do, McKenzie and her friends put together talent shows and reenactments of their favorite movies to perform for their parents. Dancing, (poor) acting and comedy skits became the norm in the Green household. During her homeschooling, McKenzie had tight-knit friendships; one of which being with another musically intrigued young girl. Together, they played melodies they had written on the piano and began developing poetic skills in attempt to build their own songwriting abilities. ​Her first solo performance took place at her 7th grade talent show where she performed (her mother's favorite) "In The Arms of an Angel" by Sarah McLachlan, accompanied by her own piano playing.