In Chicago Fire Season 11, Kelly Severide left the firehouse to pursue arson investigation in Alabama, causing strain in his marriage with Stella Kidd. In the Season 11 finale, Stella learned that Severide had actually finished the program and left for an ATF investigation without informing anyone. She took a leave of absence to find him. In Season 12, their reunion won't be shown directly, but Stella and Severide will return to Firehouse 51. Their first conversation after finding each other will be tense and emotionally charged. Despite the challenges, they are committed to making their relationship work. Compromises will be necessary, leading to more drama for Stellaride.