Chicago Fire is the fictional NBC drama that tells the story of firefighters,

rescue personnel and paramedics of Chicago Fire Department’s Firehouse 51.

Dawson is played by actress Monica Raymund, who’s been a mainstay since

the show premiered in October 2012. Dawson is an experienced, fast-thinking paramedic and head of Ambulance 61, and later becomes a firefighter on Truck 81. She marries fellow firefighter and captain Matthew Casey (Jesse Spencer), earning the beloved couple the nickname “Dawsey” by fans.

Raymund told My Entertainment World in 2015 that she was so excited when she got cast in the Chicago-based drama. “The audition process was pretty standard – I tested and then got the role. I was so excited to be on an action show and one where I knew I could stretch my drama chops,” she explained. “As the show was just beginning, something miraculous happened: I met my other family. My fellow brothers and sisters on this show became my blood and we fell in love. We fell in love HARD and the chemistry permeated the screen I believe. I met some of the most wonderful humans in the world who I will stay friends with until I die.”

So, what made Gabby Dawson leave Chicago Fire after a successful six-year run? Keep reading for the inside scoop on why Raymund chose to exit when her contract was up.