Noni was originally written as an American and Gugu Mbatha-Raw auditioned for the role with an American accent, but after hearing her speak in her natural accent Gina Prince-Bythewood re-wrote the character to make her British.
Felicia: [to Noni about her mother]
You know, it wasn't a monster who dragged you into my shop. It was a desperate mum who seemed like she'd do anything to make her kid's life better.