Author's Note: I don't own anything having to do with Supernatural only Arianna and Brielle belongs to me.

Huge thank you to SPNxBookworm who let me run a few ideas by her and convinced me to write this one shot. She was also kind enough not only to fix my mistakes but gave me a push in the right direction when I got stuck. Please make sure to check out her stories!

Climbing the Walls

Dean couldn't get his legs to move fast enough as he entered the hospital that held his brother. When the nurse at the desk told him that he couldn't go see Sam, he saw red and barreled through the door of the doctor's office.

"What do you mean I can't see my brother?!" Dean demanded not wasting any time with pleasantries.

The doctor gave a slight nod to the nurse who had followed Dean in and she left the two alone to speak. "Mr. Gamble, I presume?" Dean just stared at him with an unabashed look knowing that it must have been the name on Sam's fake insurance card. "Sam has been admitted. He was treated for a broken rib and lacerations."

"Ok…that's not so bad," Dean was clearly confused, he had patched up worse in a motel room so he couldn't imagine what the problem could be.

The doctor braced himself for Dean's reaction, "Your brother is currently on our locked psychiatric floor."

"You said he was in a car accident," Dean snarled not having an ounce of patience left in him.

The doctor held up a hand trying to keep the conversation calm and civil, "He was but Sam is experiencing a full-blown psychotic episode. We need to determine whether his state was brought on by the insomnia or whether the insomnia is a symptom of his condition. We've given him as much as medically possible but he still won't go under." He paused for a minute and watched as Dean took all the information in. "Did you know about the insomnia?"

"The not sleeping is…is kind of new," Dean admitted softly running a hand over his face, "Can I see him?"

The doctor gave a sympathetic smile and led Dean through the locked doors that could only be opened by hospital staff, "When you're done go see Judy at the nurses' station and she'll let you out."

Dean nodded and stood in the hallway watching his brother through the window on the door. He couldn't blame Sam, hell, he was half-surprised it took them this long to wind up here after all they have seen. But Dean himself was nearing his breaking point and losing Sam would have put him over the edge. Their whole lives had been surrounded by loss; their mom, dad, little sister, Ellen, Jo, Ash, Rufus, Castiel, and most recently Bobby. He couldn't, wouldn't, lose Sam too.

Three years ago

"Ari, it's not safe," Dean pleaded with his younger sister. "You need to stay where you are." He paused a minute to take a deep breath as he heard her sobbing relentlessly on the other end of the phone. "Arianna, I promise when this is over I'll come get you…I…" he sighed and closed his eyes for a brief second, "…I just need to stay sharp, this is an all-or-nothing kind of thing and I can't be worrying if you're alright or not."

"Dean, please," she cried hysterically into the phone. "I'm not a little kid anymore. I can help just, please, don't leave me here."

"You'll always be a kid to me, buttercup," Dean chuckled a little as he readjusted the phone. "I'll see you soon."

Dean ended the call and shoved the phone back in his jacket pocket with more force than necessary.

"That went well," Sam commented lightly.

Dean huffed and pressed his foot down on the gas pedal, ignoring the quick climb of the speedometer. "Let's get this over with."

He would never be able to explain to her that they were trying to stop the apocalypse; she'd only worry more than she had to. Arianna was born and raised a hunter just like her brothers but at the end of the day she brought the job home with her. Nightmares were a constant occurrence and the alcohol did little to numb her fear.

Now

Dean was on his way to talk to a man named Emanuel that one of Bobby's contacts suggested but he couldn't get Ari out of his mind. He smiled sadly remembering one night when she had come back to the motel room with blue streaks in her hair; he'd all but choked on his beer while Sam had stared like a deer in headlights. That was Ari though, always trying to be different, wanting something to make her stand out from the crowd of people, wanting to be unique. She was the complete opposite of her older brother, Sam, who did everything in his power to blend in and be normal. The color would change on almost a weekly basis and soon it wasn't just streaks of color here or there it was a whole head of bright green or orange and even pink at one point to which Dean called her Princess Bubblegum until she decided it was time for a new color.

The piercings came shortly after. First it was just the ever common ones like her earlobes until soon after both ears were lined with various hoops and studs then her nose, eyebrow and lip. All which Dean fought tooth and nail with her about getting, but she would flash him those deep brown eyes and he would eventually cave making Sam smirk at how wrapped around his finger she really was. That was until she wanted her tongue pierced and Dean promised to dig her an early grave if she even thought about it again.

Dean's chest ached as he thought about the last thing he'd ever said to her. He had made a promise to come back for her, to go back to that dingy motel room and take her anywhere she wanted to go, but instead when he and Sam returned she was gone. The room was in shambles when they got back and then they saw the blood.

The brothers spent the next six months turning over every stone, every pebble searching for their baby sister. Both had separately gone to the crossroads ready to deal, Castiel had been trying to locate her his own way, Bobby researched spells and incantations that could be used but it all left them with no answers and worse yet, no sister.

Back at the hospital

"Time for meds, Sam," the nurse smiled cheerfully as she walked in his room with some water and a small paper cup with pills on a tray. He easily swallowed the medication too tired to even question what it was. She smiled again and patted him on the shoulder, "Why don't you take a walk down to the dayroom today? Maybe some exercise will tire you out."

"Yeah," Sam replied with disbelief but as Lucifer stuck his tongue out at him from the corner of the room he realized a change of scenery might be nice.

He kept his eyes on the outdated floor tiles as he shuffled his way into the large room that had a few tables and chairs along with some books and easels set up for patients to paint. Sam had always felt like a freak growing up but standing in the middle of a psych ward with Lucifer riding shotgun almost felt like fate.

"C'mon, Sammy, let's be each other's best friends," Lucifer over exaggerated as he picked up some string that was lying around to make bracelets with. "Do you want blue or red? Oh, what's it matter anyways; I know you want a brown one."

Sam closed his eyes and took a deep breath. He wasn't going to answer, he wasn't going to acknowledge him and then maybe by some miracle he would disappear. Sam scuffed the slippers the hospital provided over to one of the chairs and plopped himself down.

"Hey, you're new."

Sam focused on the girl that seemed to appear out of no where and after he glanced around the room he realized she was talking to him and slowly nodded.

"Bri, time for group," one of the nurses called from the doorway.

The girl groaned meeting Sam's eyes as she started to walk away, "Get out while you can," she winked.

Sam quickly made his way back to his room. Once there he slid down the wall and pulled his knees up to his chest like a small child. "No, no, no," he muttered to himself. It couldn't be her, he'd take Lucifer any day but please God not her. Not Arianna.

"Sam, I hate these one-sided conversations. Come on, buddy," Lucifer raised his fists in the air out of aggravation. "Engage, Sam! You...me...locked ward. Is it me, or is this just like the Cage?"

"Just stay the hell away from me!" Sam shouted covering his ears as he tightly closed his eyes.

The next day came and Sam still hadn't slept but this time as soon as he had his medication, he made his way to the dayroom to wait for her. It took twenty three minutes for her to come into the dayroom; her smile more prominent than he had ever seen as she chatted with a few of the other patients. Her hair was sandy brown like from when they were kids and there were no piercings anywhere that he could see. Was this really Arianna or did he just want it to be?

Another girl came and sat next to him but Sam was only concerned about one other person, "Can you tell me who that girl is?"

"Brielle?" the girl questioned with a shrug. "She's been here for awhile. I don't know what happened to her but I overheard the doctors saying it's the worst case of amnesia they've ever seen." She started walking her fingers up Sam's leg, "So, my room or yours?"

"Whoa," Sam shot back in his chair causing a loud screeching noise. "Uh, no. I'm good."

The girl bit her bottom lip seductively, "I bet you are. You've ever done it in a hospital bed before? The restraints are amazing."

"Holly," a nurse approached with a disapproving look, "what have we talked about?"

"Men are friends not toys," Holly replied sounding like was a broken record.

Sam took that opportunity to get as far away from Holly as possible and while he was making sure she wasn't following, he bumped into someone knocking them to the ground.

"I'm so sorry," Sam reached his hand out to help them off the ground but froze mid-way when he saw…her. No. This wasn't possible. Ari was…was dead, wasn't she? But for once, he didn't care. This was his sister even if she was just a hallucination. "Ari?" he called out as he held out a hand to help her up.

He half expected some witty comment that she picked up from Dean but instead she smiled and took his hand, "Thanks, but you must have me confused with someone else. I'm Brielle."

"Amnesia girl, right?" Sam joked, not caring if she was just in his head, he'd waited too long to be able to see her, to talk to her again.

She was about to answer when a nurse called him over to the desk, "Sam, you have a phone call."

Sam shuffled over to the desk and put the receiver to his ear with a sigh, "Yeah?"

"Heya, Sammy, how you holding up? Counting any sheep yet?"

Sam was too tired to even fake a laugh, "Dean…I…"

"What, Sam?" Dean became completely serious on the other end of the line.

"It's not just…him anymore," Sam replied knowing Dean would understand who he was talking about. "I…I'm seeing her now too…Dean, I'm seeing Arianna."

Dean was silent for a few seconds, "Just hold on, Sammy, I've got someone who can help. I'm on my way."

The call ended and Sam looked around the dayroom praying she was still there. Hell, he'd even paint a picture with her if that's what it would take but he couldn't spot her. Lucifer lit a firecracker and tossed it on the floor making Sam flinch at the noise. Sam wasn't sure what Dean had gotten himself into but he prayed to God he would show up soon.

Later that same day

Dean had been blown away to find out that Emanuel was in fact Castiel. The two walked into the hospital hoping it wouldn't be too late to save Sam. They found him lying on his bed looking like a shell of the man they once knew.

"Oh, Sam...I'm so sorry," Castiel walked over and placed a hand on Sam's head trying to heal him. "I should never have broken your wall, Sam. I'm here to make it right."

Dean waited anxiously by the door but nothing happened. "So, what? You can take out demons again but you can't fix Sam?!"

"There's nothing left to rebuild," Castiel answered taking a step back so he was standing closer to Dean, "The pieces got crushed to dust by whatever's happening inside his head right now. I'm sorry. This isn't a problem I can make disappear."

Sam seemed to snap out of his daydream and realized for the first time he wasn't alone in the room, "Dean, you're here."

"Yeah, Sam, I'm here," Dean forced a smile, trying to keep his emotions in check.

Sam suddenly stood from the bed and grabbed the sleeve of Dean's jacket, "There's something you need to see." Somehow, Sam felt like his sister was real. He didn't know how but the hallucinations felt different, more painful, more sinister. Brielle…no…Arianna hadn't felt like that. He wasn't completely sure if she was in his head or not, but he had to make sure. He just had to.

"Sam, slow down," Dean tried to pull out of his little brother's grasp but it was no use as he was guided down the hallway and into the dayroom; Castiel following closely behind. "Alright, I'm here. What's going on?"

"Wait," Sam put up a finger and glanced up at the large clock on the wall. "She'll be here in a minute." Dean looked at his little brother with complete sadness. He thought about breaking him out and driving the two of them off the Grand Canyon when Sam's face seemed to light up and a smile broke out across his face. "She's here," Sam pointed to Brielle who had just finished her group session.

Dean thought he was going to lose his lunch right there on the floor, "Ari?"

"You can see her?" Sam questioned becoming completely serious, "It's not in my head? She's really here? It's really her?"

Dean couldn't answer any of his brother's questions as he blatantly stared at the girl from the other side of the room. "Cas?"

Instead of replying Castiel walked right up to the girl and tapped her on the shoulder. She turned with a smile on her face, "Hi, can I help you?"

"You don't know who I am?" Castiel asked tilting his head to the side and then motioned to where Dean was standing. "What about him?"

Brielle peeked around the man in the trench coat and shook her head, "No, I'm sorry I don't. Should I?"

"Walk with me," Castiel all but commanded as he turned on his heels and walked back to Sam's room where it would be more private. She went with out question and offered a small smile to Sam as he and Dean followed wondering what was going on. Once it was just the four of them Castiel turned to Dean, "I may not be able to fix Sam but I should be able to restore her memory."

"Ari, what happened to you?" Dean questioned as he went to hug her but she took a step back.

She frowned, looking apprehensively at Dean, "I don't know why you are calling me that, my name is Brielle."

Dean didn't want to scare her away so he stayed in his spot with his hands up to show he wasn't a threat. "No, you aren't. You're Arianna Winchester. Your birthday is January twenty ninth. Your favorite color changes from week to week. You stole the school mascot in high school. You have a birth mark on your left hip and a scar on your right arm from falling off your bike when you were six years old."

Brielle brought her left hand up to run her fingers over the raised skin on right arm. Had she finally met someone who knew her before she came here? "Who are you?"

"I'm your brother," Dean replied feeling his chest tighten that she had no idea who he was. He motioned over to where Sam had sat back down on the bed too tired to stand any longer. "He is too."

"And him?" Brielle pointed to Castiel.

"Just a friend," Castiel glanced at Dean, "At least I used to be." He took a step towards her and this time she didn't move as he placed a hand on the side of her head. "Are you sure you want to remember?" Brielle thought about it for a minute before biting down on her bottom lip and nodding. "Alright, this won't be pleasant."

A bright white light filled her vision before every detail of her old life came crashing back to her with such force her legs gave out from underneath her. She grunted as she rubbed the side of her head and blinked a few times.

"Buttercup?" Dean questioned softly.

He nearly forgot how to breathe as she got off the floor and launched herself into his arms. "Dean!"

Dean wrapped his arms around her as tight as they would go, afraid that if he let go she wouldn't be there anymore. Castiel knew what he had to do, the Winchesters had been through enough and it was time all three of them were together again.

"Sam, I'm not able to fix what happened…but I may be able to shift it. And if I can't tell you again I'm sorry I ever did this to you," Castiel sat down on the edge of the bed and placed his hand on Sam's forehead.

Dean and Arianna watched in shock as Sam went rigid and his eyes flew open to reveal a bright red light that traveled from his head, through Castiel's arm and into Castiel. Sam gasped as the incessant pounding in his head finally disappeared. "Dean?" he called out, seeking the one person that he knew would hold onto him.

Dean looked relieved as Sam seemed to be…Sam. Not Lucifer riding his melon Sam, but his baby brother. "I'm here," he said as he held his brother's arm to keep him steady. All three Winchesters turned in unison to see Castiel cowering against the side of the bed muttering a litany of 'not real' with his eyes shut tight.

Sam's heart ached for his friend because he now understood that Castiel had transferred the madness from his head to his own. "Cas," Sam tried reaching out for the angel who shoved him away in fear.

"Come on," Dean said as he pushed Sam out the door and held onto Ari's arm as if she might vanish into thin air. He hated leaving his friend behind but he knew that his siblings always came first and he'd solve this problem later.

It had taken three long years, going to hell, a mental hospital, and an angel but Dean, Sam and Arianna were once again together driving down the road in the Impala.

The way it was always meant to be.