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A few months later…

Addison was in the kitchen packing lunches for the girls and Lily was eating breakfast at the table. Mark came in and poured himself coffee in a travel mug. He didn't even say anything to them. Addison stood in front of him so he couldn't leave the room.

"Good morning."

"Morning."

"Can you take the girls to school?"

"No. I have an early surgery. I have to go."

"Again? That's the third day this week."

"Sorry." He walked around her and left. Addison went back to making lunches.

"Does daddy still love us?" Addison turned to look at her.

"Yes of course he does. He's just a little too busy for us right now." Kaitlyn came in.

"Can you take me to get my learners' permit? Dad said he can't this week."

"I can't. I'm sorry. You have to have a parent or guardian with you."

"Why can't you be my parent or guardian?" She sounded angry.

"I'll tell you what. If you read the book and study hard this weekend, I will find a way for you to get your permit next week."

"Thank you."

"Okay. Lunches are ready. We need to leave in 5 minutes."

When Addison got to work, she looked at the surgery board. She was upset to find out that Mark's first surgery still wasn't for another hour and a half. Callie walked up next to her.

"Mark's up to something."

"Good morning to you too."

"He leaves the house early, comes home late, ignores his kids. This morning he told me for the third time this week he had an early surgery. I got the girls up and ready and took them to school, got here, did what I needed to and now I'm looking at the board and his first surgery isn't for another hour and a half."

"Are you worried he's cheating?"

"I am now."

"Oh come on. You haven't thought about it. Both of you cheated before."

"Well, the time we spend together between the coming home late and the leaving early doesn't really suggest that he would need anyone else."

"Ahh. I don't know what he's up to. I'll spy for you."

"Thanks."

Addison went down to the cafeteria to grab something quick for lunch in the middle of her busy day. She heard Mark's laugh. She looked over and saw him having lunch with an attractive blonde woman. He looked like he was having more fun than he's seen him in a while. They were joking and laughing. He reached out and touched the woman's arm. She watched for a minute and then left, upset.

***

Addison found Mark in the hallway. She barely looked at him.

"You need to pick up the girls from school. I have a surgery."

"I can't. I'm working really late tonight." He walked away from her. She didn't know what to do. She loved the girls, but they weren't her kids. It wasn't her responsibility to always pick them up from school. She found Derek.

"Hey."

"Hi."

"What are you doing this evening?"

"Nothing."

"Can you pick the girls up from school, give them dinner, and maybe do bed? I have to work and Mark's being a jerk."

"Or I can pick them up from school, feed them lots of sugar, and have them bouncing off the walls when you get home."

"Well, it's a school night so I'd prefer the first option, but if the second is all you can do that works to."

"Sure, I'll get them. I'll keep them alive and happy."

"Thanks. I'll be home as soon as I can."

Addison walked into the house and threw her stuff down angrily. Derek came out from the other room.

"Hey. You're making all that noise after I worked so hard to have them in bed."

"I know. I'm sorry. I appreciate it." She started walking into the living room. He grabbed her hands to stop her and made her look at him.

"Add. What's wrong?"

"I'm going to kill Mark."

"What did he do this time? Leave the seat up?"

"Things haven't been as good as they were. He's not coming home tonight. He gets up early and leaves for work and comes home late. The girls barely see him. He doesn't do anything to take care of them. This morning I asked him to take them to school. He told me he couldn't, he had an early surgery for the third time this week. I found out he was lying when I got to work. At lunch, I saw him laughing and eating with a blonde woman. I can't take it much longer. I moved in because he was ready for a committed relationship. I thought having the girls here and everything that's happened, that this time it would be for real, even if we turned into a boring couple with two wonderful kids." She started crying. "I love those girls so much, I just don't know how much more I can do if he isn't going to try." Derek pulled her in for a hug.

"Everything will be okay." They stayed like that for a few minutes. Their foreheads were almost touching.

"Why can't he be more like you?" Derek leaned in and kissed her. She didn't object. They kept kissing more and more. Each one more passionate. They moved to the couch, neither one pulling back.

Two months later…

Addison pulled Callie into a closet as she walked down the hallway.

"What?" She looked up and saw Addison. "Oh you. Why am I in here?"

"I have a problem."

"Okay. What kind of problem?"

"I think I'm pregnant."

"Oh Addison that's great!"

"No. It's not."

"Why? I thought things were getting a little better."

"They are. It's just. I don't…I don't exactly know who the father is."

"Addison! What did you do?"

"It could be Mark's. It's a good possibility."

"Or?" Addison made a face.

"Derek's."

"NO?"

"Yup."

"When?"

"When things were really bad and the first day I saw Mark and the new plastic surgeon together."

"Oh."

"What are you going to do?"

"I don't know. That's why you're in here."

"First you should probably find out for sure."

"Yeah. Then?"

"You could get a paternity test. Or you could just tell Mark and let him raise it whether or not it's his. Then the child has a father and you don't ruin two relationships."

"Yeah. I don't know. It's probably best if it's Mark's. Derek and I are divorced, Derek has Meredith, Mark and I are together. Plus Derek and I had sex once. Mark and I, well, let's just say a few more times than that."

Next day….Addison was feeling very sick. She couldn't keep anything down. She was exhausted. She was sitting on the bed when Mark came in.

"You still sick?"

"I'm late."

"It's okay you're sick. I think the chief will understand."

"No I'm late. Like a few weeks late."

"Oh. What are you saying?"

"I'm saying I think I'm pregnant." She put her hands in her head. "How could I let this happen?"

"It's not like it's the worst thing in the world." She was quiet for a minute

"We're barely making it as a couple. You have two girls who you can't take care of without a lot of help. Are you saying that this is a good situation to bring a baby into?"

"No, but we can make it work. You want a baby. I know it. You tried for years."

"I wanted a baby with Derek." They were silent.

"I don't know what to say Addison. I'm trying to be positive and supportive here."

"I'm sorry. It's just I tried for years, but it's not happening at the best possible time."

"At least it will be gorgeous."

"Mark."

"What? You're beautiful and I'm just off the charts." He grinned. Addison giggled.

"Could you be any more full of yourself?"

"Hey. I got you to laugh."

"I'll get a pregnancy test done at work today."

That night….

Mark came home after the girls went to bed. He went right into the bedroom.

"I'm pregnant."

"I thought you would be."

"Are you happy?"

"Yes."

"You don't seem very happy."

"It's not real yet."

"Are you going to be a better father now?"

"I'm trying."

"Not hard enough."

"I'm doing what I can. I'm a surgeon. I have work too."

"I'm a surgeon and I somehow manage to be here to feed the girls dinner and put them to bed most nights."

"I've done this twice."

"Exactly. I don't want it to be a repeat of either of those times."

"Why?"

"Why? Seriously? You got them both pregnant and then left before either kid was born. Yeah, you went back to Elizabeth when Kaitlyn was born, but you weren't the father you could have been. You barely saw Lily as a baby and when you did you brought her to us. Yeah, you were better with Kaitlyn, but you still didn't know what you were doing and you didn't try. I just want you to try harder."

"Okay. Can we argue about this tomorrow? I'm tired."

"Fine." She rolled over so she wasn't facing him.