Unlike most Auradon kids, she is much more open-minded about having the four wicked descendants attend their school, and is sympathetic to their plight. Compared to the other kids, she is the most normal.
She is also strongly implied to be the individual who sets up the secret camera in the web series School of Secrets. Her voice appears at the beginning, saying "Alright. Good to go", and at the end, saying "Be good Auradon. Someone's watching".
She tells Mal, Evie, Carlos, and Jay that whenever she was feeling sad, her mother would bake her chocolate chip cookies and make her laugh to cheer her up.
In Descendants 2, Lonnie is very strong-willed and really wants to be a part of the R.O.A.R. team, even though it's all-male. She also accompanies Jay and Carlos to the Isle of the Lost when she hears what happened to Ben. Her martial arts skills are shown and Jay takes an interest, making him step down as the Swords and Shields team captain and making her the captain.
After graduation, Lonnie joined the pro league R.O.A.R. team for Northern Wei; thus, leaving her very busy.
- Lonnie is the second girl Mal gives a magical makeover to after Jane, having offered to pay fifty dollars, which Evie needed for clothing material.
- Lonnie is the main suspect of being the mystery girl from School of Secrets.
- Lonnie's name means "ready for battle" in old German.
- Jay makes Lonnie captain of the R.O.A.R. team, taking advantage of the rules that exclude girls from joining specifically state "a team shall be comprised of a captain and eight men".
- Similar to how Audrey was absent in the second film, Lonnie is absent in the third film; due to being busy on the professional R.O.A.R. team for Northern Wei.