<P> Kelly Severide is a fictional character on the NBC drama Chicago Fire . As his shift ` s lieutenant at Firehouse 51, Severide is the leader of Rescue Squad 3 . Severide is portrayed by Taylor Kinney . </P> <P> Severide graduated at the top of class at the academy and held the record for the youngest firefighter to make squad when he was 23 years old . He and his long - time colleague and close friend Captain Matthew Casey of Truck 81 have known each other since their days at the fire academy but have a falling - out over the death of their friend and colleague Andy Darden, whom Severide has known since childhood, over a botched - up call, which is where the pilot picks up . They work things out by the end of the season . </P> <P> The son of CFD Captain Benny Severide (Treat Williams), Kelly was raised singlehandedly by his mother, Jennifer Sheridan (Kim Delaney), after Benny left the family when Kelly was in elementary school . Although Kelly has since reconnected with his father, they still share a love - hate relationship . He is often known to the "white shirts" (high - ranking officers) as Benny's son but never used his father's name to advance his career, instead carving out his own reputation as a highly competent firefighter . </P> <P> His charismatic personality makes him a popular figure with both his colleagues and the ladies . He tends to be casual with his men and can be seen at the squad table or in the lounge chatting or playing cards with the rest of the firehouse . Despite this, he tends to keep his private problems to himself and lets it simmer, which often worries his chief . In contrast to Casey, he is highly adept at reading people, especially his own colleagues, and his observation skills have come to the fore in several arson investigations; in season 2, he correctly predicted that Hadley had been targeting the men of 51 and that Candidate Rebecca Jones, who committed suicide just months after graduating from the academy, lacked the discretion and inhibitions to truly excel as a firefighter (although she was later revealed to suffer from clinical depression). </P>

Who plays severide's parents on chicago fire