Tuesday the dalmation has been appearing on the show for the last four years

Chicago Fire's beloved canine companion Tuesday has sadly passed away, leaving cast, crew and fans of the show devastated.

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The dalmatian - whose real name is also Tuesday - died on Sunday 22 May at the age of four from kidney issues, just days before her last appearance on the show.

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Announcing the sad news, her trainer Christine Mahaney penned on Instagram: "It breaks my heart to share that Tuesday passed away on Sunday, May 22, due to unforeseen kidney issues. The love from you, Tuesday's fans, over the past 4 years has been immense."

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She continued: "Allowing her into your homes and hearts will forever be cherished. Tuesday loved working on set and being a part of the family. Her tail never stopped wagging. She truly was very special."

Fans were left heartbroken by the news and were quick to offer their sympathies and fond memories of Tuesday. Taking to the comments below the post, one said: "I am so sorry for your loss. Tuesday was a wonderful addition to the 51 family and I enjoyed watching her with them. She will be sorely missed."

Tuesday joined the show back in 2019

Another added: "Oh god. This is devastating. Tuesday was the cutest member of 51 and we all love her and always will. May she rest in peace," and a third added: "Rest in peace sweet girl. I adored watching you on #ChicagoFire. You're the best addition to that house. I will miss you immensely."

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Tuesday's final appearance on the show will be in Wednesday's season ten finale, which will focus on the wedding of firefighters Kelly Severide (Taylor Kinney) and Stella Kidd (Miranda Rae Mayo). It's expected that all of Firehouse 51 will be at the nuptials, Tuesday included.

As fans will know, Tuesday was introduced into the show back in season seven as Darren Ritter's (Daniel Kyri) beloved canine companion who suffered from separation anxiety and so was always hanging around the firehouse. Since then, she has become a fan favorite as well as the 51's official mascot.

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