"Good Morning" Meredith sung happily as she skipped up to her husband and kissed him softly. Standing beside him, she looked at the OR board trying to figure out why he was so deep in thought. "Bad day ahead?" she asked warily. Derek always had that sort of look on his face when something was wrong and this morning could be no different. With any luck it was just the emergency craniotomy that got him up at 4am this morning still lingering now that it was almost 7:30am.

"My name is on the board for a surgery that was supposed to start an hour ago" Derek commented bluntly "It's for an intestinal tumour resection on a twelve year old girl" he continued reading the bored as his confusion grew. Meredith too found where he was reading and wondered why his name was beside it. Reading the board again, she saw that the name written was a 'Shepherd, L' not Derek.

"It says Shepherd, L not Shepherd, D"

"Shepherd, L?" he repeated until all the pieces of the puzzle fell into place "Lauren"

"Lauren?"

"The fourth and final Shepherd sister" Derek read where his sister was operating and walked off leaving Meredith standing alone wondering what was going on. Pulling on a mask from the scrub room, Derek marched into his sister's OR and crossed his arms sternly "What the hell are you doing here Lauren?"

"Good to see you too big brother" she laughed softly looking up for only a moment before continuing to operate. Dr Bailey, Karev and Avery looked from Lauren with her British flag scrub cap to Derek and back again warily like they were about to be in the middle of World War Three.

"You didn't know your sister was here?" Dr Bailey asked lightly as she continued to help Lauren operate on this twelve year old girl's tumour.

"I didn't tell him I was the new Paeds Attending either" she chuckled softly

"You're what?" Derek boomed causing a couple of the scrub nurses to jump. "If this is some sort of joke I want nothing of it and if you're here to spy on me for Mom just like Nancy before you then you can report back that all is fine. I don't want to see her or you for that matter"

"Derek shutup" Lauren snapped and quickly took the clamp from the scrub nurse and barked at Avery to retract more before looking up at her brother "For once, this isn't about you so you can either stand there and shutup or get the hell out of my OR. I don't have the patience to argue with you right now" she growled and continued operating.

"How dare..." he began

"Stats are dropping, down to 80%" Bailey piped up quickly as the monitor started to beep

"Derek get the hell out or go tell this kids parents that you've just killed their child" Lauren barked before Derek finally got the point and stormed out of the OR. Digging her hands into the small child's body, Lauren found what the problem was and fixed it before the girl started to crash. She resected the rest of the tumour and any other cancerous cells in the area and assessed her work before starting to close. Stepping back from the table, Lauren let the nurses prep the girl for recovery and stretched out her shoulders. Ripping off her gloves and mask, she followed Bailey, Karev and Avery into the scrub room to wash her hands.

"I think you're my new favourite Attending" Avery laughed as he handed Lauren a bar of soap and the four surgeons started washing their hands. Dr Bailey coughed loudly and started down Avery jokingly "After Dr Bailey of course" he chuckled

"Is it because I just saved that kids life or because I yelled at the famous Derek Shepherd?"

"Yelling at Dr Shepherd" Alex and Jackson chimed in unison with a laugh.

"Well I'd have to say how you managed to get the whole tumour. When we first opened her up I thought we'd have to leave some of it there" Dr Bailey marvelled as she threw a couple of towels at the Residents and ordered them to go check on their patient in recovery

"Good work in there guys, I'll see you up on the Paeds ward for rounds in about half an hour. I have to deal with my brother" she laughed as they left. Picking up a towel for herself and handing one to Bailey, Lauren leant back on the sink trying to think of how to even start talking to Derek. He was in a foul mood which wouldn't help.

"If you don't mind me asking, why didn't you tell Dr Shepherd you were coming?"

"If I'd told him then he would have ordered me back to Connecticut to Mom and our eldest sisters but I haven't been to the east coast in almost five years. I don't think passing over it to get from London to LA really counts" she laughed and pulled off her scrub cap. Playing with it in her hands, she stretched it out to see the many Union Jack images all over it

"I used to have a bright purple scrub cap with stars all over it. I gave it to an eleven year old I treated in London about six months ago because the beanies she was wearing just got too itchy. Her Mom made me a new one so I would always remember London whenever I planned to come home. Lily was one of my success stories; she survived Leukaemia and then a tracheal tumour" Lauren continued before sniffing and wiping a tear from her eye

"I walked into the hospital two weeks ago and Lily was in the ED in respiratory distress. I didn't get all the cancer and a new mass had grown incredibly fast and cut off her breathing. She crashed before I could even get her to the OR, I couldn't revive her. I came to Seattle because my big brother got shot and no-one decided to tell me til six months after it had happened. Lily didn't tell her Mom she was having trouble breathing because she had a dance recital. I could have done something if Lily had just told someone; just like I feel like I could have done something for Derek if someone had just told me what happened. Derek might not want to see me but I'm not going anywhere"

"You should tell him exactly that. All of it even the scrub cap story" Bailey smiled weakly and rested her hand on Lauren's in comfort "I'm sorry about Lily"

"Just some of the pain you have to deal with when you're a surgeon specialising in Paediatric and Neo-Natal Oncology. My little sister Amelia tells me I'm a sucker for a war I'm never gonna win"

"I think you just won that battle though" Bailey chuckled referring to the life they'd just saved "She's probably never going to have to worry about cancer ever again"

"I hope so" Lauren smiled "Thanks again for your help in there. I understand why Arizona offered you the fellowship now. Shame you turned it down" she chuckled and walked toward the door "Wish me luck"

"You don't need it just tell him about Lily"

Thoughts?

Will Derek lighten up to his sister being around?

Note: Lauren replaces Stark as the Paeds Attending when Arizona goes to Africa