A\N: So a few of you have been asking me if I'm going to keep Matt's past the same as it is on Chicago Fire or if I'm going to change it. I'm planning on keeping the general idea of it the same and changing it around. You'll find more about his past in this chapter and upcoming chapters as well.

Disclaimer: I do not not own Chicago Fire, Chicago PD, NBC or Global

Spoilers: None

Warnings: None

Chapter 10

Arm propped up on his desk tried to ignore the temptation of his cell phone and listen to Sergeant Voight talk about their newest case.

"Detective Casey, you with us?" He banged a hand on his desk causing Matt to jump slightly.

"Yeah sorry Sir," He stuffed his phone into a drawer to avoid further distractions, "I'm listening,"

"Right," He curtly nodded and went back to explaining the details of the murder.

"We really think the sixteen year old son could've killed his father?" Casey glanced at Antonio as they walked up to a high school "You heard what Voight said according to the uniforms the son caught him cheating on the father last week. That seems like motive to me."

"Maybe the father was a jerk. I think the families better off without him."

Antonio turned and glanced at him curiously, they had only been partner for a few months but he knew that wasn't his usual attitude at all. In fact ever since they started talking about the case he'd been on edge.

"Still…." He trailed off and stopped talking as they walked into the main office and explained why they were here.

The teenager was pulled out of class and they were escorted into a meeting room, present was a school counselor who had to sit in on the meeting as Liam was still a minor according to the law.

"Look my father was just this guy," He began, "I stopped expecting anything out of him a long time ago. I'm I sorry he'd dead? No. Did I kill him? No. But I like whoever did."

"I understand you're father wasn't a very nice guy but we was murdered so we still need to investigate," Matt tried to explain.

"So if my Mom finally killed him you're going to put her away? What kind of justice is that?"

"Not very logical I know," Matt again tried to stay professional, "But sometimes the law isn't."

"Well I'm not going to help you put my mother in jail. From where I'm standing my jackass of a father deserved what he got."

"You know," Antonio finally spoke, "You're looking more and more like a suspect."

"I don't care! Just leave me alone!" He exclaimed, "Can I go now? I think English class will be more exiting then this."

"Go, go but here," Matt handed him a card, "You think of anything call."

"Yeah, yeah," He rolled his eyes and left.

Thanking the school officials for there time Matt and Antonio left

"Hopefully he doesn't do much covering or he'll be charged with conspiracy," Antonio said as started the car.

"I don't think he's thinking about that right now, He's scared and he wants to protect his mother, I really don't blame him."

Turing off the ignition Antonio stared at him, "Wanna explain?"

"No."

"Okay," He started the car and they road back to the district in silence.

The rest of the morning Matt wasn't in a good mood and as most of the evidence began pointing to the son as the murdered Matt stormed off into the locker room.

Antonio followed him and leaned against the end of the rows of lockers as Matt punched the wall in frustration "I'm gonna guess this case hits something personal for you. I'm I right?"

"Yeah."

"We all have those.'

"Not like this."

"Well unless you want to take some time off, you should probably talk to someone."

"I don't need to talk. I don't talk about my family."

"Right," Antonio took a deep breath in and then let it out, "Well at some point you and I both know Gabby is going to want to know something."

"Can you just let me handle this?" He slammed his head against his locker, "Just tell Voight I'm taking fifteen minutes to clear my head."

"Sure Man," Antonio walked out of the room taking his cell phone out of his pocket as he went.

Around two o'clock Officers Burgrass and Roman pulled Liam from school and brought him into the station for an official interrogation. Neighbours had told them that over the past couple of weeks they'd heard more and more heated exchange between the deceased and his son.

Across from Antonio and Matt Liam sat with his arms folded and a cross look on his face. With him were a social worker and a lawyer.

"You're here because witnesses said you haven't been getting along with your father, " Antonio explained his presence, "We just want to know from you what you and your father argued about."

Liam laughed sarcastically, "That'll take some time Detective."

"We're trying to help you Liam, no need to get defensive."

Rolling his eyes Liam said, "Your father ever hit you Detective? Tell you you're worthless? Did we beat you up?"

"No," Antonio answered honestly.

Liam laughed again, "Well mine did. So yeah we fought he was frustrated because now I was strong enough to hit back whenever he came after me or my Mom; he was loosing control and he was angry. You know what he told me? He told me he'd shoot me if I didn't stop defending my mother."

Matt clenched his fists around the table, an action that didn't go unnoticed by Antonio and he didn't even need to glance back to the one-way mirror when there was a knock on the door and Voight walked in.

"Go take a walk Casey," He ordered, "I'll take it from here.'

Sighing but doing what he was told Mat stood and walked out of the room. He walked into the bullpen.

"Someone's downstairs to see you," Nadia told him.

"Thanks, Matt nodded and made his way down the stairs, shocked to see Gabby sitting on the bench.

"Gabby? What're you doing here?" He wondered as he walked up to her and kissed her.

"What?" She made a face, "I can't come by? You've seen the firehouse. Besides, "She lowered her voice, "I've always wanted to see upstairs."

"Sorry unless you're a suspect you can go up," He told her, "It's just an office though."

She shrugged, "Yeah I know. So you busy?"

"In the middle of a case but you wanna come over to my place tonight?"

"Sure," She gave him one last kiss and turned to leave.

Watching her walk away Matt smiled to himself and jogged back up the stairs. When he arrived back at his desk Antonio was sitting at his, "Thanks Man."

He looked genuinely confused, "What for?"

"My girlfriend was downstairs."

He shrugged and lowered his voice a notch, "I might have sent a few text messages. Thought you needed someone to talk to."

"Well thanks."

He waved it off, "I don't want a partner who isn't on his game."

"Yeah," Matt chuckled and returned to work.

By the end of shift they still hadn't found enough evidence to convict anyone for the crime so they all silently agreed to stay a little longer to figure it out. Everyone knew, including Matt, that the son was their best suspect as he had the means the motive and the opportunity. Still it wasn't until nearly ten o'clock that Halstead finally got word from the crime lab.

"The print found on the gun matches the son's."

"Go get him," Voight ordered, the squad went to the house to pick him up.

When they put the cuffs on him the mother was hysterical, "NO! PLEASE NO!" She begged and Lindsay and Casey had to hold her back so she didn't do anything.

By the time they got back to the District they were all emotionally drained. That's why they were all glad when Voight said, "Paperwork can wait. All of you go home."

Antonio didn't have to be told twice, with a quick wave to everyone he was the first one to go to his locker and collect his things. Olinsky, then Casey who texted Gabby to tell her he'd be home soon followed him. Doing that he realized felt right for some reason.

"Hey Casey, you up for a drink?" Halstead asked as Matt walked back into the bullpen, "Some of us are going down to Molly's."

"I would but I have a date, I might stop by though tomorrow night with my girlfriend."

"Okay man," Halstead said and left down the stairs talking to Lindsay.

TBC

A\N: Reviews make me very happy! :D