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After Matthew Casey and Sylvie Brett's Wedding, Revisit Their Chicago Fire Romance

Grab the tissues and revisit some of "Brettsey's" cutest moments as a couple on Chicago Fire

By Jessica White & Megan Lasher

There's nothing One Chicago fans love more than seeing two Chicago heroes fall in love. And when it comes to Firehouse 51, there's one fan-favorite pairing whose slow-burn romance left audiences with a lot of hope. 

How to Watch

Watch Chicago Fire Wednesdays at 9/8c on NBC and next day on Peacock.

Chicago Fire's Matthew Casey (Jesse Spencer) and Sylvie Brett (Kara Kilmer) — lovingly called "Brettsey" by fans — have had a complicated platonic and romantic history. 

The duo were friendly from the beginning of Season 3 when Brett first arrived on the Chicago team, connecting through Brett's then-partner Gabby Dawson (Monica Raymund), who ultimately married and later divorced Casey. Because of her friendship with Dawson and Dawson's relationship with Casey, Brett intentionally did not pursue anything more than a casual friendship with the Truck 81 leader.

However, after the end of his marriage and in the wake of Dawson's departure in Season 7, Casey was dealing with his broken heart and he and Brett became much closer, leading to the genesis of "Brettsey." That culminated in the two becoming a couple in Season 9, a long-distance romance, and a surprising proposal at the end of Season 11.

Season 12 delivered the moment Chi-Hards had been waiting for — a Brettsey wedding.

Violet Mikami (Hanako Greensmith), Sylvie Brett (Kara Killmer), Chief Wallace Boden (Eamonn Walker), Matt Casey ( Jesse Spencer), and Kelly Severide (Taylor Kinney) appear in Season 12 Episode 6 of Chicago Fire.

When did Sylvie Brett and Matthew Casey get married on Chicago Fire?

After officially getting engaged in Season 12, Episode 1 ("Barely Gone"), Brett and Casey got married in Season 12, Episode 6 ("Port in the Storm") in a ceremony at an aquarium officiated by Chief Wallace Boden (Eamonn Walker). Brett's partner, Violet Mikami (Hanako Greensmith), served as her maid of honor and Casey's long-time friend, Kelly Severide (Taylor Kinney), served as his best man.

"Sylvie Brett, getting here to this place was the toughest battle of my life," Casey's vows began. "But it was worth every moment because we're here now. You are my port in the storm." 

During Brett's vows, she agreed: "It’s just like you said, we were meant to be. And we were meant to be a family."

Brett had one more thing to say, to her guests. "All I wanted was for this wedding to be simple, intimate, and perfect," Brett told them, full of tears. "And it's all of those things."

Sylvie Brett (Kara Killmer) and Matt Casey ( Jesse Spencer) appear in Season 12 Episode 6 of Chicago Fire

Below are some of the other beloved highlights from Casey and Brett's complicated, close-knit relationship, which picked up in Season 7.

When did Matthew Casey first try to ask Sylvie Brett on a date on Chicago Fire?

After Dawson moved to Puerto Rico at the start of Season 7, Brett approached Casey and asked, "How could you just let her go?" Casey told her that he was even more upset than she knew.

In the dramatic Season 7 finale ("I'm Not Leaving You"), fans saw the first potential Brettsey tease.

Casey saved a young boy and his pregnant mother from a car wreck and, after watching Casey interact with the kid, Brett stared at him longingly. "Jump him already," Brett's partner, Emily Foster (Annie Ilonzeh) said after catching sight of the glance. 

RELATED: Brett's Future Love Life Will Have 'Fun Surprises,' Chicago Fire Producers Say

Later in the episode, Boden invited Casey to a double date dinner: "Sounds like I need to find a date," Casey said.

He immediately walked over to the garage, where he watched Brett and Foster pull in and high-five. "Brett, so..." Casey started to say as he walked over to her, but was interrupted by Christopher Hermann (David Eigenberg) and Darren Ritter (Daniel Kyri).

"What did you want to ask me?" Brett asked when Hermann and Ritter's conversation subsided. "Let me get back to you later," Casey said.

But later, he saw Brett hug her ex, Chaplain Kyle Sheffield (Teddy Sears), and assumed they were back together, so he did not ultimately ask her to the dinner.

Sylvie and Casey embracing each other

When did Sylvie Brett first leave and then return to Chicago?

Brett ultimately did end up back together with Sheffield, who proposed and asked her to move to Indiana with him. She did so at the beginning of Season 8, but the couple broke up and Brett returned to Firehouse 51 in Season 8, Episode 3 ("Badlands"), much to the team's excitement. 

Upon seeing her, Casey gave Brett a hug and said "51 just hasn't been the same without you." The two exchanged a short, loaded glance, a nod at their near-miss moment from the Season 7 finale.

What happened between Sylvie Brett and Matt Casey in Season 8 of Chicago Fire?

In Season 8, Episode 9 ("Best Friend Magic"), Dawson made a surprise appearance back in Chicago and caused a rift in the escalating closeness between Brett and Casey.

Brett ran into Casey in the firehouse shortly after his reunion with Dawson — which included a dance —and asked how it went. Casey said it went well, to which Brett responded, "That's so, so good to hear." Always hyper-aware of her partner's micro-expressions, Foster mocked Brett, "So, SO good to hear", to which Brett replied, "He seems happy. That makes me happy." 

Brett had an eventful end to Season 8 when she reunited with her birth mother, Julie (Kelly Deadmon) — who shortly thereafter announced that she was pregnant with Brett's half-sibling. Julie believed that Casey and Brett were a couple, and doubted Brett when she told her that they were just friends.

Unfortunately Julie passed away giving birth to Brett's half-sister, Amelia, in Season 8, Episode 18 ("I'll Cover You"), but Casey was there to hold Brett through the aftermath. 

When did Sylvie Brett and Matthew Casey first kiss on Chicago Fire?

In the Season 9 premiere ("Rattle Second City"), Brett and Casey's close relationship became even closer when Brett was held at gunpoint during a rescue at the beginning of the episode and forced to treat one of two criminal brothers. The brother later died, and Brett feared that the man who held the gun to her head would come back for revenge.

She asked Casey to spend the night with her, and the two ended up playing games and laughing the night away. 

Brett tried to give Casey an out, saying "It's getting really late," but Casey interrupted her: "I'm staying, Sylvie," he said while smiling. 

In Season 9, Episode 2 ("That Kind of Heat"), Brett's ambulance was run off of a bridge by the brother she feared would hurt her. Casey and Truck 81 ran to the rescue (with Casey jumping out of the vehicle to get to Brett faster), opening up another chance for Casey to take care of Brett. In the aftermath, Brett told Casey, "It's always been you." 

Later in the episode, as tensions between the two escalated, Casey showed up at Brett's house to ask why she was avoiding him. "So I wouldn't end up doing this," Brett said, kissing him. 

But then she asked him if he still had feelings for Dawson, and he couldn't answer... so he left.

What happened after Sylvie Brett and Matt Casey kissed in Season 9 of Chicago Fire?

Casey expressed an interest in pursuing a relationship with Brett in Season 9, Episode 3 ("Smash Therapy"), but she demurred, worried about his feelings for Dawson.

Instead, Brett ended up pursuing a relationship with Casey's nemesis Greg Grainger (Jon-Michael Ecker) for part in Season 9, and he asked her to define her relationship with Casey.

"You two had something, didn't you?" Grainger asked.

"I don't know. It's a long story," she replied, flustered. "It was somewhere between something and nothing, but..."

Grainger interrupted: "I could tell there was more going on." 

In the middle of Season 9, Casey was injured at work feared the worst after suffering from headaches and vision difficulties as a result. Brett, however, was by his side for all of his medical appointments and he was eventually cleared for work again, bringing the two closer.

In Season 9, Episode 15 ("A White-Knuckle Panic"), Casey told Brett that he was in love with her and only her. In Season 9, Episode 16 ("No Survivors"), she admitted she loved him, too, and they ended up kissing and ultimately going back to her place.

The two were a confirmed couple in Season 10.

When did Matthew Casey leave Chicago and move to Oregon on Chicago Fire?

Fans of Chicago Fire know that Brett and Casey's romance likely couldn't survive when Casey decided to move to Oregon to be a stand-in parent for his late teammate Andy Darden's (Corey Sorenson) two sons. Long-distance relationships are rough, but Chi-Hards kept their fingers crossed for Brettsey to make it work.

In their heartfelt goodbye in the show's 200th episode (Season 10 Episode 5, "Two Hundred"), Casey told Brett, "But you and me, I want to keep being you and me."

When did Matthew Casey first return to Chicago and Sylvie Brett on Chicago Fire?

In a heartfelt reunion between the couple at the wedding of Casey's partner, Kelly Severide (Taylor Kinney), Casey and Brett acknowledged the plight of being in a long-distance relationship. They danced together during the reception and talked about whether or not it was still worth staying together. 

“How much longer can we keep this up?” Brett asked.

Casey replied, “I don’t know, but we’re together tonight.”  

Kara Killmer As Sylvie Brett and Jesse Spencer As Casey dancing together

When did Matthew Casey and Sylvie Brett break up on Chicago Fire?

After the distance began taking a toll on Brettsey, they decided to split up to allow the other to grow. After several long-distance visits, love letters, and phone calls, Brett broke up with Casey over the phone in the show's Season 11 premiere ("Hold On Tight").

"Our stars just didn't align," she told him. 

Kara Killmer Walks Through the Brettsey Proposal | Chicago Fire | NBC

When did Matthew Casey and Sylvie Brett get engaged on Chicago Fire?

Brett’s personal life was a focal point in the Season 11 finale of Chicago Fire. After she decided to adopt a baby, her then-boyfriend, Dylan (Christopher Allen), broke up with her, saying they were in two different places. Meanwhile, Casey — who was in Chicago helping out on a case at the time — caught wind of this.

Realizing he wasn't over Brett, he showed up to her house at the end of the episode and proposed, saying he wanted to combine their families.

"Sylvie Brett, we were meant to be," Casey said. "Will you make me and the three kids the luckiest family in the world? Marry me." 

In the Season 12 premiere of Chicago Fire ("Barely Gone") Brett said yes to Casey's marriage proposal.

Everyone at Firehouse 51 couldn't be happier for the couple. A hopeless romantic, Brett was a glowing bride-to-be, buzzing with wedding plans. She revealed to her coworkers that their wedding would be in Chicago and "family-only" — which included their 51 loved ones, of course. 

While wedding bells were a joyful development for Chi-Hards, Brett had one piece of sad news for her 51 family: After the wedding, Brett was moving to Portland with Casey. Her colleagues were sad to say goodbye to Brett but knew she and Casey deserved to ditch their "long-distance" status. 

Sylvie Brett (Kara Killmer), Matt Casey (Jesse Spencer) Kelly Severide (Taylor Kinney), Stella Kidd (Miranda Rae Mayo) pose for a photo together

When did Sylvie Brett leave Chicago and move to Oregon on Chicago Fire?

Brett and Casey's wedding in Season 12, Episode 6 ("Port in the Storm") was one for the One Chicago history books, as Firehouse 51 celebrated the couple becoming husband and wife as well as a family. After a rousing reception at Molly's, complete with cake, selfies, and lots of dancing, the firefighters and paramedics all gathered outside to give Brett and Casey the send-off they deserved.

As their loved ones tossed rice in their honor, Brett and Casey hopped in the car and onto the next chapter of their lives. 

Watch Chicago Fire on Wednesdays at 9/8c on NBC

Originally published Mar 25, 2023.