Ellie Kemper has bright red hair and even brighter eyes. She has a few freckles and a cute button nose. Ellie has an excitable personality. She is happy, fun-loving, and bubbly. She loves being a witch and learning more about how she can use her magic.

Ellie is a half-blood. Her father, Emmett, is a strong wizard, who married the love of his life, a Muggle named Marcia. Ellie's mom was strict on her growing up, knowing that she would need to stay focused, determined, and hard working to successfully balance her life in the Muggle and Wizarding worlds. However, Ellie tends to enjoy her father's company more. Emmett would always use magic in front of Ellie to impress her and cause her to get excited about exploring and learning.

Ellie's first instance of magic occurred when she was 6 years old. She was running around, playing with her imaginary friends in her backyard. As she was running around, she climbed a tree and out of excitement, jumped out of it pretending she could fly, before logic could kick in and tell her that she could not. As she hit the ground, her parents ran outside fearing the worst. But Ellie was not hurt at all, and described the fall like she was "jumping on the bed", though she should have been hurt from the height of the tree. Her parents looked at each other at that moment and knew she was a witch.