A/N: This is my first shot at writing a fanfiction, a one shot at the moment, but if people like it I'll continue it as I have plenty more ideas for the story :) Written by me, Beta'd by my sister :) Based on the scene where Addison arrives to Grey's Anatomy, Series 1 Episode 9 :) Enjoy!

Disclaimer: I don't own Grey's Anatomy or any of it's characters

Derek's POV

There I sat, finishing off some last minute work while I waited for Meredith. I was dreading this conversation; the need of a 'talk' in a relationship usually ended in disaster. I glanced up and noticed her coming round the corner; I put my laptop away and smiled at her.

"Hey, long day; somewhere out there is a steak with your name on it, and maybe a bottle of wine."

She smiled "This is why I keep you around."

I swallowed the lump in my throat and went for it "We need to talk."

"Wine now, talk later."

I sighed with relief; she was averting the subject "You trying to make me drunk, so you can take advantage of me?"

She laughed that laugh, that beautifully addictive laugh; I couldn't help but smile with her "I think I'm starting to like this rule thing."

"Me too." I replied

Excited about the evening ahead, I helped her with her coat and picked my bag up from the floor. That's when I noticed her; a flash of red hair at the other end of the room. I could have recognised that hair anywhere. A black coat was hanging from her shoulders; trust her to come in black. The colour of doom, I thought to myself; something that I undeniably would be in a few moments. I frown and a weight forms in my stomach, until I spot the boy clutching her hand. He'd grown so much since I last saw him; I'd missed a birthday. His ten-year-old face didn't look much different from his nine-year-old face; his dark hair and blue eyes remained the same like mine, but he was at least an inch taller. I didn't even have time to feel guilty as I turned to Meredith, remembering where I was and what was about to happen.

Before Addison could say anything, I looked at Meredith. Her eyes had followed mine to the woman and the boy facing us "I'm so sorry."

She frowned as he ran towards us and jumped into my arms; I crouched to meet him and couldn't help but be over the moon that he was excited to see me too. When I left I had no idea I would be gone for this long. I hated that I had left him with her.

"Hey there, my little man."

He held the hand that I was using to ruffle his hair "Hi dad, you miss me?"

"Of course I did, so very much."

"Guess what?" I looked at him expectantly "I lost another tooth, see."

He showed me the gap where his tooth used to be, I smiled with pride the way any normal father would. Suddenly she's right there in front of me and I catch Meredith's expression out the corner of my eye, it is a look of total shock and confusion.

"Urr…why don't you go over there and have a look at the fish tank? There's even a Puffer fish."

"Cool."

Everyone's eyes followed him over to the tank; Meredith's eyes fixed back on me, as did Addison's. I didn't want to look back, my eyes stayed on my son a while longer, then back at the mess I had created.

"Addison, what are you doing here?"

"Well you would know if you called me back," She turned to Meredith with that look in her eyes "Hi, I'm Addison Shepherd …and that boy over there is Leo Shepherd"

"Shepherd?" Meredith echoed

I knew that the next words out of Addison's mouth were not going to be good. At all.

"You must be the women who is sleeping with my husband and his father." She said it as a statement, instead of a question; she already knew the answer.

Meredith's eyebrows knitted together, she didn't say anything as she walked away. It felt worse that she didn't speak.

"Your hair is longer." She broke me from my thoughts and stroked my hair; I batted her hand away.

"What are you doing here, Addison?"

"What are you doing here?" She deflected the question back at me "You just pick up and leave; your friends, your practice, your son, you had a life in Manhattan."

"Had, I had a life there, not anymore… and I didn't leave him."

"That's funny I thought you had, because we haven't heard anything from you and he certainly missed you. Now you have a girlfriend here. She seems sweet, very young though, attracted to the whole brain surgeon thing."

A wave of guilt hit me, I had left him. I talked myself down; no, I was going to go back for him. And she has no right to talk about Meredith, she didn't know anything about her.

"Have you come here to win me back because it won't work and bringing Leo just wasn't fair to him."

"That's right, Derek. I flew all the way here just to get you back! Relax, I brought Leo because I had no choice; I have no one to help me anymore. Trust me, I would like no better than to keep him away from you. But I'm here to consult on a TTSS case you guys admitted last week, Richard called me and so he will brief me on the case and we will both be out off your hair sooner then you can say."

"Richard knew you were coming?" I cut in

"He didn't tell you? The hair is great by the way. Come on Leo, lets go find uncle Richard" She held a hand out to him

"Okay, bye dad"

I just stood there, totally bewildered by what had just happened, and watched her walk away with my son.

Another A/N: Thank you for reading and please review! Tell me if you'd like me to continue and if you think the story is written well. Constructive criticism is welcome, but please be gentle as it is my first time. :) Thanks again!