Nina Metz, The Chicago Tribune

CHICAGO — DuShon Monique Brown, an actor best known for her performances on the NBC show “Chicago Fire,” died Friday at a hospital in suburban Olympia Fields, Ill., the Cook County medical examiner’s office said. She was 49.

The cause of death was not disclosed.

“The ‘Chicago Fire’ family is devastated to lose one of its own,” executive producer Dick Wolf said. “Our thoughts and prayers are with DuShon’s family and we will all miss her.”

On the NBC series, Brown’s character, Connie, was a stern-faced delight and a steadying influence on a group of co-workers prone to getting into one mess or another. On Thursday’s two-hour episode, she memorably and wordlessly picked up a non-work-related fax for the firehouse gang and simply gave them a long, withering look before handing over the piece of paper. Brown could do a lot with a look, and the show’s writers and producers made the most of that talent.

“We are devastated by the loss of a very talented and kindhearted soul,” said Brown’s manager, Robert Schroeder. “She brought laughter and joy to many, and she will be greatly missed.”

Cast and crew often talk about the sense of family among those who work on “Chicago Fire,” and in 2016 Brown, a Chicago native who grew up on the South Side, told the Huffington Post that “people are always asking me about my kid and how my day is going and they are all so very sweet and kind.” Noting her master’s degree in counseling and background in social work, reporter Andrew Cristi jokingly asked how she’d feel about a spinoff called “Chicago Ed” or “Chicago Shelter,” to which she replied: “I’m there! If they pull that show out, I will be an actor and a consultant! Trust me.”

The website FanSided has a vertical for the Wolf NBC shows set in Chicago and earlier this year featured an appreciation of Brown, who “imbues Connie with not only that ‘don’t mess with me’ kind of authority, but a real personality. The character wouldn’t work if she was just a snarky assistant telling everyone what to do … She loves what she does and she loves the people that she does it with.”

Last year, Brown told the website Hidden Remote that when she was cast in the role of Connie on the NBC series, “my character didn’t even have a name. She was a noun. She was Secretary and it was a one-liner. What was exciting was (I) was auditioning for a Chicago show, but it was also the possibility that she could maybe develop into something.”

Brown graduated from Whitney Young High School and the University of Illinois at Urbana-Champaign, earning a graduate degree from Governors State University.

A longtime Chicago stage actor, Brown performed at the Goodman, Victory Gardens, Lookingglass, Drury Lane, MPAACT and Pegasus Players. Her previous TV work includes the recurring role of infirmary nurse Katie Welch for 13 episodes on “Prison Break” (2005-07) and one-time guest spots on “Empire” and “Shameless.”

Chicago theater actress Carla Stillwell remembers meeting Brown in the 1990s shortly after college, when the two became good friends. “She was a brilliant actor,” Stillwell said, “but she was also so goofy. We used to get in so much trouble from the stage managers we worked with because we were cutting up so much.

“She was just a ham. And she was truly loved.”