At the start of Season 4, Chief Boden is under surveillance and investigation, Chili along with the team support his boss before he is arrested and demoted as Chief and replaced by Dallas Patterson. Jessica “Chilli Chilton delighted fans from the moment she debuted in Chicago police. She gave a performance as lively as an informant that the Fire showrunners decided to cast her as the informant's twin sister. She joined Fire as an ambulance driver in season 3, and was created to be a main character in the future.
Chili was a character who always struggled with her drinking habit and was fired from her job for drinking at work. However, the most recent on-screen outing caught many by surprise when Boden (Eamonn Walker) unceremoniously fired Chili (Dora Madison). Disciplinary action had taken a long time to come when Chili began to arrive late and drink a lot after the sudden death of his sister. But off screen, the decision to start Chili was surprising given Madison's promotion to the regular series early in the season after joining the team as Brett's new paramedic partner at the end of season three.