The character could fundamentally change the show.
There was a lot that went down during the Chicago Fire season 12 finale, but the one that had the biggest implication on the show’s future was the revelation from Jack Damon (Michael Bradway). He told Kelly Severide (Taylor Kinney) that they were half-brothers, despite Severide not knowing that he had any other siblings.
This was a revelation and a relief in some ways, as the fear some fans had was that Damon was going to be Severide’s secret child. It was much more effective to introduce him as a brother, and it actually sets the stage for a very different Severide in season 12.
Jack Damon could help Severide mature as a character
Severide is at a crossroads in his career. He doesn’t have the gung-ho firefighter attitude he once did, but he’s made a point of doing less arson investigation. He’s a respected veteran within Firehouse 51, yet he will not be taking over the chief position from Wallace Boden (Eamonn Walker).
The most clear path forward for the character, besides mentor, is family man. And the introduction of a new member of his family heralds this transformation. Severide had a complicated dynamic with his late father, Benny (Treat Williams), but he told Stella Kidd (Miranda Rae Mayo) that he was ready to have children in the season 12 finale.
Damon is seemingly different from the rest of Severide’s family
It was a huge revelation for both the audience and Kidd, as Severide had always made it clear that he didn’t want to become a father. The arrival of Damon could help Severide work through the family issues he still has, and build a healthy familial bond for once.
Severide’s sister and father were very much characterized by their transience, and their refusal to stay in one place for long. Damon, on the other hand, came to 51 because he wanted to get close to Severide. It’s a huge difference, and it will do great things for both of them. Assuming, of course, that Damon does stick around.
