Disclaimer: for sure, don't own it.

"Hey, Peter. I'm Dr Grey, I'll be taking care of you today.", Meredith muttered, a smile on her face as she glanced at the little boy with purple dinosaur pyjamas, thick dark hair covering his left eye as he gave her a small smile.

Peter Davies was nine years old and had been admitted two years ago for nausea, headaches and vomiting. A few scans had promptly revealed a medulloblastoma. Dr Martinez had been the surgeon in charge of his case, assisted by Dr Shepherd. Her mentor had been able to remove the tumour with clear margins and had also inserted a VP shunt. The surgery followed by a rigorous round of chemotherapy and radiation had resulted in the little boy being declared cancer-free.

Meredith vaguely remembers observing his surgery from the gallery, remembers the envy creeping up on her at recognizing Shepherd.

But two years later, the tumour was back. This time it was situated in the spine.

This was, she assumed, any parent's worst nightmare.

Mr Davies stood at the foot of his son's bed, arms crossed, similar dark hair while Mrs Davies stood on Peter's left, tightly clutching his hand, an apprehensive look in her eyes.

"Dr Martinez wants us to repeat his scans before moving ahead."

"Okay, yes. Of course.", Mrs Davies whispered.

"Derek!", the little boy screeched at her fellow surgeon's entry. Meredith watched as relief overtook the parents when Derek sent a small smile their way. And for a second, a part of her doubted her presence in the room.

"Hey, big guy.", Shepherd moved toward him and indulged in a fancy and rather complex handshake.

"It's good to see you, Derek.", Mrs Davies whispered.

"You too. Rob. Mel."

"We are going to crush you tomorrow. C-R-U-S-H. Total destruction.", Peter said, animatedly flailing his arms, halting the exchange between the adults.

"Sure, kid", he rolled his eyes, a grin overtaking his features, one that crinkled his eyes, one that made him look almost..bearable. "You don't beat the best team in the world."

"We're the best team in the world!", he yelled, balling his tiny fists, a determined gleam in his eyes.

Derek only winked at him in response resulting in a very disgruntled little boy. She smiled at his antics, a little amused by the relationship he shared with her arch-nemesis.

"Sorry about that. Petey's sort of our in house baseball expert. And fan."

"Meredith.", Peter began.

"Dr Grey, Peter."

"No, no. It's fine. You can call me Meredith."

"See, Mom. You can call me Petey, Meredith.", she watched as he switched gears, changed tactics, a mischievous glint appearing in his soft amber eyes. "Meredith, I know Derek's your friend and stuff but you can't trust him."

Trust was definitely not something she associated with Derek Shepherd.

Well then, neither was friend.

He motioned for her to come closer and he slowly leaned forward, whispering, conspiring, "He'll say that the Yankees are the best but it's the Dodgers, you have to know that's it's always the Dodgers."

He settled back and fixed her with a brilliant smile, his eyes shining and she knew then, that Peter Davies would grow up to break several hearts.

Derek scoffed beside her and Meredith couldn't help but beam at Peter, "You know what? I don't know a whole lot about baseball but I'm gonna take your word for it and say that..the Dodgers are the best team in the world."

"Yes!", he excitedly pumped his fists, blowing a raspberry at Derek.

"Easy there. We should hold judgement until tomorrow's game. Because right now, you need new scans, bud."

"Fine.", he muttered, visibly deflated. Derek fetched a wheelchair and pushed it towards his bed.

Meredith hoped as she watched the chattering nine-year-old slip into his wheelchair that them working together wouldn't turn out to be a complete disaster.

Because Peter Davies -with his baseball obsession and charming smile-deserved better.

Meredith sat in the gray chair, lightly swivelling. She could vaguely make out Peter in the doughnut-shaped MRI machine while she could distinctly recognize Derek, standing in a corner with his arms crossed, eyebrows pinched as he watched over the procedure.

They'd been in here a while, waiting for the scan to finish. The little boy hadn't moved, had remained extremely calm so far. She knew MRIs were claustrophobic and even most adults had a hard time through them yet, Peter hadn't made a single sound.

Her heart clenched at the assumption that his composure was possibly a byproduct of the countless scans he must have experienced in the past owing to his diagnosis.

She had, after all, never liked working with kids. It was too hard, too painful.

You need to toughen up, Meredith. Get a thicker skin. Otherwise, you're just setting yourself up for failure. But, honestly, I doubt if it would make any difference.

The door was suddenly pushed open, propelling her back to reality as Derek pushed himself into the chair beside her, a puzzled look on his face.

"I still don't understand why you were put on this case.", he grunted distastefully.

"Don't get your panties in a bunch over this, Shepherd. It's obviously because I'm a better surgeon than you."

He snickered, leaning forwards, eyes intently fixed on Peter, "Whatever helps you sleep at night, Slinger."

That stupid nickname. Derek Shepherd somehow always managed to fuel her rage.

He invariably made her feel like spending hours setting up a Christmas tree, meticulously picking each ornament and then dousing it with gas and setting fire to the whole thing.

The name had originated when on their first day as interns, on their first day working together Meredith hadn't been afraid to set him straight, hadn't hesitated to explain to him, in great detail, what he'd done wrong. Which had, according to him, made her look like Yosemite Sam.

The small, angry red man.

Full of crap really.

Yosemite Sam had been a gunslinger.

Hence, the name.

He alternated between Slinger and Sling, depending on his moods and sometimes, he resorted to simply calling her Yosemite. The name was, in her opinion, petty and so so stupid but it had always managed to annoy her. Which served its purpose, unfortunately.

But she could play this game, they'd become experts at it at this point. He lunged, she dodged. She advanced, he sidetracked. It was how they worked. This near-perfect dance they indulged in.

Rule 4: Never back down. Never let a blow go unanswered.

"Oh, trust me. I have some very..colourful ways to help me sleep at night.", she said, smirking. She beamed as he blushed, a soft pink filling his cheeks.

Jackpot.

"Derek?", Peter's unsure voice through the intercom prevented her from going any further.

"Yeah, bud?", he replied, pressing the black switch to activate the mic.

"I..don't feel so good. Can you do it?", he mumbled, his voice breaking towards the end.

"Of course.", Derek glanced at her, a look akin to fear in his eyes before he cleared his throat and put most of his weight onto the white table, his hand clasping the mic.

"-two balls and no strikes. Taylor leads from first, he delivers and flyball to the left! It's on its way and it's gone! A homerun for Justin Turner! When they needed a home run the most, they turned to Turner. A two-run shot and the Dodgers take a 4-3 lead and this crowd is stunned.", Meredith watched him with his boyish grin, he'd transformed his voice a few octaves lower, had paused at the right moments and had sounded almost like an actual announcer. "This trip around the diamond was gladly sponsored by Daniel's Jewellers and after every home run, go to any one of the hundred-plus Daniel's-", Peter's heady giggle forced her to avert her gaze from Derek's face as he too, finished.

"You okay now, kiddo?", His voice returned to his normal tone albeit a much gentler one.

"Yep. Thanks, Derek."

"No worries."

She avoided his eyes instead lowering her head, intently staring at the threads protruding out of her old coat.

She didn't recognise this Derek, this kind, gentle man who acted like a baseball announcer for little sick boys, who comforted family members and who agreed to work with the woman he hated for his patient.

To her, Derek Shepherd was calculating and opportunistic, a shark. There was a reason she despised him, a reason why she could never even entertain the possibility of being anything but an enemy to him.

But this Derek- tossed all that she understood about him-out the window.

She couldn't be wrong. She couldn't be.

His behaviour today had perplexed her yet, if she knew anything at all, she knew that Derek Shepherd was a master of pretence.

And she wouldn't fall for it. Not again. Never again.

The tumour had grown, faster than they'd anticipated, faster than it should have.

Meredith stood on the side with a glowering Derek as Dr Martinez attempted to explain this to the Davies out in the hallway, away from Peter's ears.

"I..I don't understand.", Melanie looked up at her husband, wrapping her arms around her torso tightly, pain etched onto her face.

"What do we do now?", Robert asked grimly. Liam paused for a moment, staring at the distressed parents.

"We will figure out a plan and get back to you. Very soon.", he slowly squeezed Melanie's shoulder, a warm look on his face.

"We'll run a few more tests-"

"Dr Martinez, he's seizing." They were hurrying into the room before the nurse had even finished her statement.

"Push one of Phenobarbitol. Now!"

She heard Melanie wail in the background as she fell to the ground, sobbing, Robert soon joining her.

Meredith and Derek moved to stabilise Peter as his body flailed mercilessly.

"Is the pheno in?"

"Yes, doctor."

"Push another!"

A grand mal seizure. He was having a grand mal seizure.

It was relentless, countless spasms taking over his body. This wasn't the tumour, couldn't be it. It had invaded a large portion of his spine but was nowhere near his brain. Something else was going on in his body, something wreaking havoc.

The seizure slowly subsided as the drug took control, his heart rate returning to normal, his body calming down.

Meredith took in her surroundings, looked at the sweet little boy, at his helpless parents, at Derek and Liam.

They needed to figure out what was going on and they needed to fix it. Fast.

"Today has been such a weird day.", Meredith muttered taking a seat beside Cristina, her lunch in front of her, untouched as she concentrated on the journal in her hands.

"Okay?", she said without looking up.

"What happened?", Izzie asked,holding her half-eaten sandwich.

"Okay, so Shepherd was trying to steal my surgery in the morning right? We went to Martinez and he suggested that we work together and Shepherd agreed."

Cristina turned her body towards Meredith slightly. She knew Cristina was listening. Her best friend acted indifferently but she knew that she was always listening. Alex on the other hand was doing paperwork and she knew that he wasn't listening.

"Then what happened?"

"Right. It's this adorable kid called Peter who has the tumour and Shepherd had worked on his last surgery so he was being his usual asshole self about it but-", she took a moment to eat while Izzie gazed at her with raised eyebrows."But guess what? Shepherd was really nice to him. It's crazy, like they bonded over baseball and he even did a whole announcer thing for the kid when he got scared during the MRI."

"Oh."

Meredith paused at Izzie's disappointed sigh, confused, "What?"

"It's just...Mer-", she looked around the cafeteria table uncomfortably refusing to meet her eyes.

"What, Izzie?"

"What Izzie wants to say", Alex began with a sigh, "is that Shepherd is a cool guy. Hence helping the kid out-not crazy."

"No he isn't.", Meredith scoffed loudly but a glance at her friends proved that she was in the minority over this. "Seriously?"

"Look, Mer if you knew him, you'd agree.", Izzie said, shrugging her shoulders, "Not that that means I agree with anything Karev has to say."

"I do know him! And he is an asshole. Cristina-"

"Please, please someone help me.", Lexie appeared in the chair beside Izzie, practically collapsing.

"I cannot work in peds. It is killing me, watching all these little sick babies. Please give me something. Anything.", she widened her eyes at them and then resting her head on the table.

"I have nothing."

"I work in peds."

"Don't have time for all this, Three."

Her little sister turned her gaze on her giving her the signature doe-eyed look.

"Mer? Anything. I will assist you. In aneurysms. Tumour resections, brain bleeds. I will be your intern. Just please."

"Lexie I-"

Brain bleeds.

"Lexie, you're a genius!", Meredith said, leaping to her feet.

She could hear her sister's desperate wails as she rushed out of the cafeteria, her lunch half-finished. She couldn't pay head to her right now, she had to talk to Martinez.

Brain bleeds.

Lexipedia really was a genius.

Meredith had been looking for Dr Martinez for a few minutes now. He wasn't in his office neither was he on the OR board. She knew it wasn't his shift in the ER so she went around checking the conference rooms on the surgical floor. Maybe he had a meeting. That she hoped could wait because this was urgent.

She'd had no luck finding him in the first two conference rooms, she just hoped he was in the third because if he wasn't- she was screwed and more likely, Peter would be, too.

She pushed open the cinnamon coloured door only to find Derek with his head in his hands, his usually flawless hair in disarray. He slowly turned to her, hands now on his neck with frustration deeply etched on his face.

"What do you want?"

"Um, do you know where Martinez is?"

"No.", he went back to the papers strewn in front of him.

"Oh, I thought you'd know."

"Why would I know?", his voice was hoarse, as if he'd been screaming.

"Since you know, you're sorta his pet-"

"I'm not his pet", he growled, clenching his jaw.

"Sure-"

He had closed the distance between them before she could even finish the sentence, facing her with his fists clenched and teeth gritted, "This may be a joke to you but this is important. This is about someone's life. A child's life and I know you don't get it but try."

"Contrary to what you think Shepherd, Peter is the reason I'm looking for Martinez."

"Yeah? Why? Do you know what's wrong with him?"

"As a matter of fact, I do and I know how to fix it as well."

"It has to be a tumour we missed."

"It's not.", she rolled her eyes at him. He was close, close enough that she could smell his cologne, close enough that she could see his chest rise and fall with every breath.

"You don't know that. We only got an MRI of his spine."

"I do. A tumour the scans missed three days ago?", she scoffed.

"So then what is it?"

"I need to talk to Martinez first."

"That's ridiculous, just tell me."

"I can't."

"It has to be a tumour.", she could hear the uncertainty in his voice.

"It's not."

He inhaled sharply and then stepped closer, "To you, this may just be a point against me but it's not. This matters.", she could feel his angry breaths on her cheek.

"You may believe that I'm a cold, heartless bitch but what you believe isn't the truth.", she clenched her jaw, an all-encompassing rage overtaking her body while she could detect the slight tremors in his body too. "I care about Peter and I will help him.", she continued, jabbing her finger into his chest.

"You don't. I know him, I've seen him in so much pain that he threw up, I've watched his family fall apart, scared that he wouldn't wake up, I've watched them celebrate when he walked out of here tumour free. Me. What you feel is nothing. It's not enough."

"Screw you, Shepherd. You know nothing about me or what I feel so screw you.", she was in his face now, her nose almost touching his crooked one as she looked right into his anguished dark eyes.

"You-", a loud beeping sound emanating from their respective waistbands put a stop to their argument. Meredith detached her pager to check for its contents.

Code Blue. Room 2231.

Peter. Oh, God. Oh God.

They couldn't be too late. No. No.

Derek was out the door before she'd even processed her thoughts and then she was behind him, rushing through the busy hallway. She found him in front of the elevator and she watched as the fear forced him to head towards the stairwell, taking two steps at a time.

They shouldered their way through the throng of people on the pediatric floor to reach Room 2231. To reach Peter.

Melanie and Robert were crouched outside the room, arms around each other, Melanie tightly clutching onto her husband's shirt. They were both trembling, sobs wracking their bodies.

"What happened?"

"He seized again. And then his heart stopped, we've been trying to bring him back ever since.", the intern, Mia explained.

"How long has it been?"

"Five minutes."

Derek stayed to the side, frozen, his mouth opening and closing as he watched it all unfold, his eyes welled up.

"Give me the paddles.", she demanded. She needed to take control of the situation. Meredith approached the little boy laying supine on the bleak hospital bed.

Come on, Petey.

"Charge to 100!"

"Clear."

"Nothing."

"200."

"Nothing."

Come on, Come on.

She chanced a glance at Derek who now stood against the wall, his eyes shut tight.

"300!" She was met with uncertain, almost disapproving glances but she held on.

"Nothing."

"Charge again."

"Clear."

Please. Please. She could feel her heart palpitate, a dull ache beginning around her sternum.

"We have a rhythm!"

They had a rhythm. Peter had a rhythm. He was still here, still alive.

"Okay", she sighed, relieved. "Mia, get him in for a head CT, stat. And stay with him at all times."

"Yes, Dr Grey."

Meredith walked backwards to stand against the wall opposite Derek, her hands behind her back, watching him watch her. She met his ocean blue eyes, "Subdural hematoma. His VP shunt must be malfunctioning, causing a subdural hematoma and thereby the seizures. A head CT is all he needs to show that and then a craniotomy and we'll adjust the shunt.", he listened to her with rapt attention, the pieces slowly fitting for him., "He'll make it, Derek.", she whispered a moment later, the gentleness in her tone, foreign even to her.

He nodded and pushed himself off the wall, making his way to the CT room but then he stopped at the threshold, barely turning his body to her, "Thank you."

His voice was hoarse , as if he'd been screaming.

She could do this. She could do this.

Meredith Grey could perform a craniotomy on a nine-year-old with the man she despised. Without a supervising attending.

She would have to. They would have to.

Peter had coded again when they'd been getting him out of the CT machine. The scan had shown what she'd expected- a subdural hematoma. Caused by his malfunctioning VP shunt which had been put in prior to his last tumour resection to control the hydrocephalus. While they had gotten him back, Peter's ICP had been through the roof and they knew that he would need surgery immediately.

Except Dr Martinez wasn't answering his page and they were later informed that Liam had to step in for Dr Crawford since she had gone into labour. So Dr Crawford was out too. Nelson and Basu were in the middle of their respective surgeries. While Michaelson was on vacation.

That had been all the attending. Leaving them, the fifth year neurosurgical residents.

But they weren't authorized to operate without at least an attending's consent which currently, they did not possess. Meredith knew that this, this might just have some seriously grave consequences.

But Peter needed them so it wouldn't matter. Whatever happened they'd deal with it.

Somewhere along the way, Meredith had conceded. Accepted the fact that they were now-a team. Every cell in her body had protested, her brain refusing to accept Derek as an ally-even if it was only for one surgery, a few hours but then, she'd fought back.

For Peter.

"We can do this.", she said, her arms in the air, water dripping down them as she looked at Derek beside her,scrubbing.

He paused for a second before fixing her with a determined look, "No, you will do this."

"What?"

"Meredith I..I screwed up today. Froze. I wasn't a good doctor today and Peter? He deserves the best so yes, you will do this. I can be your intern; I'll hold the suction for you."

She stared at him, dumbfounded. Did he just-? He was breaking one of their unsaid rules by stepping back. She knew that he knew and somehow, that didn't bother him. Although, it did bother her. She would have to figure out this different Derek she'd encountered today. But not right now.

Right now, she had to save Peter.

"Dr Grey, can I scrub in?", her intern asked barging into the scrub room. It made him lower his eyes from hers, returning to his task at hand.

"Mia..I'm sorry but, no you can't."

"But-"

"Not this time. Work on my post-ops, Dr Watson."

"Yes, Doctor.", she left, grunting on her way out.

She didn't need her intern. Today- she had a different one.

Derek slowly nodded, gesturing for her to move into the OR first.

As she pushed open the glass door with her shoulder, she realised that she hadn't missed the guilt in his eyes nor had she missed his insinuation that she-was a better surgeon than him.

The surgery had gone flawlessly. Textbook procedure. Better than she had hoped for. And true to his word, Derek had held the suction for her. Had closed for her; had handed her instruments-had been the perfect intern.

But what had scared her the most was how in sync they'd been throughout the surgery. It had almost been like an intimate dance. He would suction without her asking him to, would make way when she needed,they hadn't needed words inside-they had just been. And that terrified her.

Because Meredith Grey and Derek Shepherd were not a team.

This, this was fleeting. This was for Peter and then they would go back to their old, petty ways.

Right?

The only reason they'd worked so good was that they were both amazing surgeons. Derek was, after all, a brilliant surgeon so of course, he would predict her moves. That made sense.

Despite their differences, the two had always harboured mutual professional respect for each other so yes, them being in sync made sense. Simply because of their acumen, their skills.

"What were you two thinking?! I'm guessing you weren't thinking at all.", their mentor screamed at them as they stood with bowed heads in his office. Liam had been livid when he'd found out about the stunt they'd pulled. Yet he hadn't reported them to the Chief.

"There was no time.", Derek replied.

Liam huffed, kneading his temple with his fingertips as the low lights in the room made his caramel coloured skin glow., "Next time, even if the world is ending, you tell me first. Clear?"

"Yes, sir.", they replied in unison.

"Come on, let's go tell the Davies that he's going to fine.", he moved past them to the door and paused right before leaving, "Great work, by the way. You make a good team."

"Actually-", but he was gone before Derek could finish whatever he was saying. Meredith followed her mentor, Derek right behind her.

By the time they reached the Davies, it seemed that Dr Martinez had already explained the situation to them. When they reached them, Melanie promptly hugged Derek while Robert repeatedly thanked her, tears running down both of their faces.

"These two saved his life today."

"We'll never be able to thank you Derek, Dr Grey.", Melanie whimpered, wiping her tears.

"Actually, it was Dr Grey. She was the one who figured out what was wrong with Peter and then, she was the one who did the surgery, I just assisted her.", Meredith stared at Derek, perplexed as he continued to avoid her gaze and then, she was engulfed into a tight hug by the couple, and Derek had moved out of her field of vision.

"Can we see him?", Robert asked as they detangled from her.

"Yes. He should be in recovery. Come on, I'll take you.", Liam led the parents towards the recovery wards, sending a sly grin towards Derek as if they were sharing a secret.

Well, the day had been weird. To say the least. She had worked with Shepherd and worked well. He'd seemed almost human to her today which again, was very strange but then, Meredith had also flown solo today. This wasn't her first time, it most definitely wouldn't be her last but as she made her way towards the resident's lounge she couldn't help the grin that appeared on her face.

Derek was walking beside her, but not quite with her.

"Me- Grey?" They were right outside the lounge now.

"Yes?", she hadn't acknowledged what he'd done earlier and honestly, she had no plans to.

"Um, do you-uh maybe wanted to get drinks?", he asked, a hesitant smile on his face.

"What?", the question practically gave her whiplash.

"Not like-no, no. Think of it like-an apology drink or drinks. For today. Because I was an ass today, you saved Peter's life and I was an ass. I never meant to imply anything about your skill, Grey. So yeah, drinks on me. If you want to.", his eyes had turned to a softer, warmer cerulean blue as he shrugged his shoulders sheepishly.

It was probably the adrenaline from the surgery still coursing through her body that forced her to nod and return his quiet smile.

"Okay, then.", a grin overtook his features. "Meet you there?"

"Mer-?"

She swivelled to face the source of the voice. Michael stood before her having replaced his mint scrubs for his navy polo and dark jeans.

"Mike." Meredith and Michael had broken up about six months ago but sometimes, they still found their way back to each other. Hence, last night.

"Mer, do you think we can talk about last night? Joe's?", he asked softly, running a hand through his thick blond hair.

Meredith stole a glance at Derek who suddenly seemed very interested in the pale walls of the hallway.

"Can you give me a minute?"

"Yeah. Of course. I'll be at the nurse's station."

She nodded, her eyes still fixed on Derek.

"Shepherd."

"Holden.", he gave her a bright smile as he walked off.

"Shepherd I-"

"It's fine.", he cut her off.

"Rain check?"

"Sure, whatever.", he briefly locked eyes with her and she noted how they had darkened to a cold, cold azure.

"Wait, -", he left her standing there, hurrying inside the lounge.

She was confused by his behaviour, more in that moment, than she had been the whole day.

If she didn't know him any better, she would say that he seemed almost hurt.

But, she did know him better.

So she left to meet Michael.

A/N: there you go. Sorry, it took so long but yes, please tell me what you guys think. I love hearing from you all and thank you so much for all the reviews!