A/N: Hey guys! I've decided to start a one-shot series, right now it looks like it'll be four chapters but that could definitely change. It'll focus on our four main characters: Casey, Severide, Dawson, and of course, Shay! (She'll never be completely dead to me.) The four of them have made life-altering decisions in their lives, and this series focuses on the possibility if they had chosen differently.

None of these chapters are related to each other whatsoever! They're all in their own universe.

In season one, Casey had decided that with Hallie never wanting kids, their relationship wouldn't have ever worked. In this chapter...Casey chose his love for his fiancée over his love for children.

Chapter One:

It was Thanksgiving. And like every year for some unlucky reason, Casey had shift. He didn't know why the days had to fall that way, but he did know that first and second watch better be thankful for always getting to spend the day with their families while Casey and the guys went on the most ridiculous calls of the year. They'd probably respond to more oven fires today than they had all year. And on top of that, they'd have to settle more family feuds than they would probably prefer. They all had their own problems to deal with, especially Casey, and they didn't want to get in the middle of other people's pathetic issues.

Although, technically he shouldn't be complaining. Lieutenant Harris had offered to cover Casey's shift for the day, but Casey wouldn't let him. Harris had three kids, a wife, two brothers, a sister, and one hell of an extended family. Harris simply would have more fun on the holiday than Casey would have, and that's why Casey currently found himself pulling the blanket off of his body at six in the morning.

His bare feet hit the cool, hardwood floor and he pulled himself up, walking tiredly towards the bathroom while he tried to rub the sleep out of his eyes. On his way, he peeked into the bedroom, where Hallie slept with her head buried in her pillow. He watched her sleep for only a couple of seconds, sighing softly to himself before quietly walking in. He pulled out a casual, long-sleeved blue shirt, a fresh pair of boxers, socks and jeans from his dresser before continuing on towards the bathroom.

He showered quickly, got dressed, brushed his teeth, and had a brief breakfast before pulling his jacket on and grabbing his keys. He picked up his brown bag that held a change of clothes and his phone charger in it before walking out the front door.

When he arrived at the firehouse, he noticed that second watch was just leaving. He got out of his truck with his brown bag hanging on his shoulder, waving to a few people he knew as they walked to their cars, ready to get their Thanksgiving started.

Casey couldn't help but become a little jealous as he envisioned them with their families. Their kids, their wives, their parents...the whole shebang. Casey didn't have any of it. He's had a fiancée for four years who has no interest in ever being a mom, a dead father, and a mother who's probably spending the day with her loser boyfriend.

Now that he thought about it, he actually didn't even know who he'd spend Thanksgiving with if he weren't on shift. Christie and Violet were probably with Jim and his family, and if he spent the day with Hallie, he knew they'd spend the whole time trying to make people believe they were happy and still trying to plan their perfect wedding.

That couldn't be more of a lie.

"Hey, Casey!" Herrmann's voice pulled Casey out of his thoughts, and honestly, he couldn't have been more grateful for his friend at that moment.

"What's up, Herrmann?" Casey wondered, waiting for the older man to catch up to him so they could finish the short walk towards the firehouse together.

"Just wanted to let ya know Cindy is coming over with the kids later and she's bringing pie. Is Hallie comin' this year or nah? Cindy has to know how much pie to bring..."

Casey shook his head, sighing a little. "No, she's going over to her sister's house, probably won't be able to stop by."

Herrmann nodded, expecting such an answer, but not knowing what to say to his Lieutenant. To be friendly, he probably would've asked how her residency was doing at the hospital, especially since the bombing a few months ago. He was genuinely curious as to what had happened to her job after that, but he didn't know if Casey was the person to ask about it.

He'd noticed a shift in their relationship in the past year or so, hell, everyone had, but it was ultimately nobody's business but Casey and Hallie's.

"Well, that's too bad," Herrmann said finally, studying his younger friend before a pair of hands smacked his shoulders suddenly. He turned around, meeting Otis' big grin and Cruz's right behind him. "Damn Otis, isn't it a little too early for that?"

He turned back towards Casey while Otis defended himself, but was saddened to see the Lieutenant already walking into the firehouse. He frowned a bit before turning his attention back towards Otis and Cruz, who had also began to defend his roommate.

In the locker room, Casey turned the dial of the lock to match his locker combination, but sighed frustratingly when the lock wouldn't open. What the hell was with this thing today? It usually didn't take him five tries to open his damn locker.

"I hope you're not still feeling those effects of that injury..."

Her voice caused his head to rise in an instant, and he managed a small smile when their eyes met. Her face held a playful grin, which let him know she was messing with him, but her eyes showed a genuine concern.

"Nah," he answered, watching as she placed her bag on the bench as she turned towards her locker. "I just..I don't know, this thing is being difficult today."

"Maybe that's because you're trying to open Kelly's locker..." She trailed off, and his eyes darted up to the top of the locker he was trying to open and when he read the tape, he sighed annoyingly.

SEVERIDE

He had indeed stopped at his best friend's locker by accident instead of his own that stood beside Severide's.

"Dammit," he muttered. He moved over a couple of inches so that we was at his own locker now, and when he tried the lock, it worked on the first try.

"Works a lot better when you get the right locker, huh?" She was being smart with him, and as usual, he couldn't help but smile at her humor.

"Whatever, Dawson," he mused, shaking his head in a joking manner as he tossed his stuff into his locker before getting changed into his Lieutenant wear.

Gabby smiled to herself as she pulled her paramedic shirt over her head, slipping on her work pants right after. As she gathered her hair into a low ponytail, she couldn't help but look over at Casey. His torso was bare as he dug out his Lieutenant shirt, and she caught herself admiring his muscular back as he turned around to put his shirt on.

Casey caught her gaze, and he could've sworn he saw something a lot like lust in her eyes, but by the time his shirt was over his head, she had averted her gaze.

She sat down on the bench, her back facing him, and bent down to put her boots on. Casey cleared his throat as he sat beside her and put on his boots as well, sneaking glances at her every few seconds.

"So uh..how's Mills?" He finally asked, his eyes now focused on the laces of his left boot as his fingers worked them into a knot.

"We're alright, I guess," she shrugged, her attention also trained on tying her boots. "How's Hallie?"

He sighed to himself, knowing he should've seen that coming after he asked about her relationship with Peter. "We're good," he lied, nodding to try to convince her, and to probably convince himself.

"Matt," she said softly, and he looked over at her, knowing she was the last person he could fool. "You know you can talk to me, right? About anything. I mean it."

He smiled a little at her, grateful for their friendship that had practically weathered it all in the past few years. "I know," he told her softly, nodding. "I guess it's just been hard lately..."

She waited for him to continue, and when he did, she didn't interrupt.

"I think it all started when I delivered that baby a couple of years ago, remember that?" Casey smiled at the memory, and Gabby didn't fail to notice the twinkle in his eye as he reminisced.

"How could anyone forget that night? That was...that was something special Casey, it really was." She smiled as she also remembered the Thanksgiving from two years ago, and she especially remembered the excitement in Matt's voice as he retold the full extent of what happened when they had gotten back to the firehouse.

"Yeah, it was," he agreed, and she then noticed that the smile he held right now was the most genuine she's seen from him in awhile. What the hell has been going on with him?

"Anyway," he continued, his smile fading as he went on with his point. "You know I've always wanted kids, it's been a dream of mine for as long as I can remember. And that night when I delivered the baby in the middle of a ten car pileup, something sparked in me. I realized I wanted kids right then, and I told Hallie that." He was frowning at this point, and Dawson gently put her hand on his shoulder, an unspoken comfort for both of them when they talked to each other like this. "But she, she told me she didn't want them at the moment. She told me she didn't know if she'd ever want them…"

Dawson carefully squeezed his shoulder, realizing that the question of having kids or not could definitely tear a relationship apart. Casey turned his head towards her, and her heart sunk further than she ever thought possible when she noticed the tears surfacing his captivating blue eyes. "I just...I feel like I've been wasting the past two years of my life," he admitted, shaking his head. "One of the only things I want in life are kids, and I'm engaged to somebody who doesn't want them. We haven't slept in the same bed in over a year because all we do is fight, and of course all of our fights go right back to the kid thing, and I just don't know what to do at this point. I've thought about ending it so many times, but something always draws us back together. First it was the Heather thing, then my injury, then Jones' suicide, then the bombing at the hospital, then the explosion a few months ago…" he shook his head, sighing heavily. "I'm just sick of making up excuses about why we should still be together, because we shouldn't be."

Gabby's hand was now rubbing Matt's shoulder comfortingly as she listened to him, not knowing what the right thing to say him could be after he was done speaking. "Matt," she began quietly, and their eyes met again. Gabby could tell he was looking for help, any kind of help, and he relied on her. It was rare when Casey opened up to her lately, and she hadn't even opened up to him about her relationship troubles with Mills.

But finally, she decided the best advice she could give him would come from her heart, from what she actually thought about the situation. "I know you well enough to figure out that you're still with Hallie because you would have felt guilty if you left her sooner without knowing for sure if your relationship with her would have worked or not. You like to explore every option, even if it doesn't benefit you in the end. It's just the kind of guy you are. You don't give up, that was clear with the Voight situation and when you were fighting for your life last December." Now her eyes were clouding with tears at the memory she didn't like to revisit often. "You put other people's needs and wants before your own," she continued thoughtfully. "It's one of the things I admire most about you. But, Matt, there's gotta be a point where you recognize what you want and what you need."

Casey swallowed thickly, nodding as he looked down at the floor again. She was right, and God, he knew it...he just couldn't believe it was actually the end.

"We've been together for seven years," he murmured, sighing deeply as he turned towards Gabby again. "I thought we were going to be together forever...and now that just seems like a joke."

He rubbed his hands over his face, shaking his head as Gabby's hand continued moving comfortingly over his shoulder.

"It sucks," she agreed, nodding sadly. "But hey, you'll rally."

Even in the mood he was in right now, Casey couldn't help but chuckle as she mocked the advice he had given Mouch months ago. "It was good advice," he defended, smiling as he playfully nudged Gabby's shoulder.

"Yeah yeah, whatever you say, Casey," she grinned, not realizing how much she'd missed his bright smile lately until now.

"Well, he did rally, didn't he? He's having the time of his life with the one and only, Trudy Platt," he chuckled again, shaking his head at the unlikely pairing.

"Well then that should give you confirmation that you too, Matthew Casey, will rally just as Mouch did," she told him, smiling warmly.

"I hope so," he agreed quietly, smiling in sincere gratitude. "Thank you, Dawson, really. I know I've been a bit off lately, but um, hopefully that'll change soon."

"It will," she assured him sincerely, finally and reluctantly dropping her hand from his shoulder. He was about to say something more when a panicked and sweating Severide jogged into the locker room.

"Casey!" He called, resting his hand on his friend's shoulder once he'd reached him.

"What the hell is the matter, Kelly?" He wondered, looking at his fellow Lieutenant worriedly.

"The oven broke, and without the oven, we can't have turkey," Severide explained, and Casey rolled his eyes. "C'mon, Matt! We need you to fix it!"

"Alright, alright," Casey told him, standing up from the bench. "Could you go get my toolbox from my office?"

"Sure thing," Kelly promised, and he began to jog towards the direction of the sleeping area.

Casey closed his locker before turning towards Dawson again, watching as she also stood up. "This goes both ways, you know."

"What does?" She asked curiously, putting her stuff away before shutting her locker.

"Talking about stuff," he told her simply, shrugging. "I mean I know we haven't really done it in awhile but I never went anywhere...I'm still here and I know I haven't been the only one acting a bit off recently."

Casey watched with concern as she bit her lower lip and looked down at the floor. "Come to Molly's tomorrow night, we'll talk then. Right now you gotta go save the day." She offered him a small smile, but it was nothing that told him she was fine, so instead he wrapped his arms around her. It took her a second, but he felt her arms around his body soon.

"Thank you for listening," he murmured softly. "And I promise I'll be there tomorrow night, and I'll give you better advice than to rally, even though it is good advice."

"I'm looking forward to it," she told him sincerely, and they both share a small smile as they pull away. "Now you better go fix that oven, because if I don't get my turkey on Thanksgiving, we're gonna have a problem."

Later that day, after five calls to oven fires and three of them containing some sort of family feud, Casey found himself sitting in the empty seat between Severide and Dawson at the table. He assumed Mills had planned to sit there because when he was done setting all of the food down and saw who was in his seat, he looked like a lost puppy dog.

"There's an open seat right here, Mills," Herrmann said, patting the chair next to him. Mills sat down and told everybody they could dig in.

"Hold up, hold up," Boden said, standing from his chair. "Two things before we start eating. One is that I think it's appropriate to say that this past twelve months has been crazy. We almost lost one of our own last December.." He motioned towards Casey. "In April we actually did lose one of our own, and we will forever remember her spirit, her strength, her skills, and of course...that cake." Everybody laughed at the memory while Herrmann just shook his head with a smile. "And only a couple of weeks later, a terrorist attack shook our city and almost claimed the lives of several of us. Then of course, in May, we were hit with our hardest obstacle yet." Severide looked down while Dawson shifted uncomfortably. "Leslie Shay will always be with us, she was a part of our family and we will never forget her, she made us who we are today." Everybody nodded in response, their minds playing their favorite memory of the blonde.

"Last thing before we start eating," Boden announces, his finger pointing at the turkey. "What should this thing be named this year?" Two years ago it had been the piss guy, then it had been McLeod, which was an obvious choice, and this year, Casey thought there was another obvious choice.

"How about Welch?" He suggested, and everybody quickly agreed.

"Then it shall be named Welch," Boden smiled, sitting down. "You guys can dig in now."

Throughout the dinner, no calls had been requesting their service, which they were all thankful for. They all enjoyed more jokes from Otis and Cruz, tried to follow Mouch's ramblings, listened to Herrmann's stories about his kids, and reminisced on old times.

Laughing so hard his stomach was hurting, Casey realized that this is all he needed for Thanksgiving. These guys were his family. He didn't know where he'd be without them, and frankly, he didn't even want to imagine. He hadn't heard a word from Hallie all day, which he figured was the best thing at the moment. A tough conversation was coming between the two of them, but it had to happen. Right now, though, he wanted to enjoy this time. If they'd learned anything throughout the years, it's that life could be taken away in a split second.

So there it is, the first one-shot of the four! I don't know how I feel about this one. Casey was a hard one for this idea, but I did the best I could. I initially wanted to include Hallie more, but yeah, that didn't happen. My Dawsey brain got the best of me.

I would love to hear your feedback! :)

Next up: In the season two finale, Dawson decided that it'd be better if she and Shay traded places. In the next chapter, she decided she wanted to take the lead on it.