After the news of her exit first broke, Killmer reflecting on her time on the show on Instagram. The actress shared a series of throwback photos shortly after the news of her exit broke. “These are the very first few pictures I took, or was tagged in, when I first came to Chicago. Going up in the Squad 1 basket was my first exposure to the CFD—some of the best firefighters in the country!” Killmer captioned the post. “The view from my very first apartment was absolutely stunning and the beginning of a love affair with the gorgeous city of Chicago!”

Her departure comes not long after her on-screen love interest Jesse Spencer left, and she is likely leaving for similar reasons. Following his Season 10 exit, Spencer told reporters that he felt it was time to start a new chapter, per TVLine. “I realized I’ve been doing  TV for a long time. I added it up, and I think this year is my 18th year of network television,” Spencer said, referencing his time on Fox’s medical drama House and his time on Chicago Fire. “I called [showrunner] Derek [Haas] and broke him the news, said I thought it was time to leave the show, and he agreed that we should at least get Casey to 200 episodes.” He continued, “It was a difficult decision because I’ve loved the show from the start, but there are other things that I would like to do in the future, and there’s some family that I need to take care of, and 18 years is a long time.”

Killmer has been married to Andrew Cheney since 2016, so it’s possible that she wants to focus on her marriage and family life, similar to Spencer.