A/N After the Grey's Season Finale boy do I need some Mark/Lexie.

Invasion

Mark had fallen back asleep while Lexie went to go speak with Alex. She knew that Mark was the one for her and she was sick of having to deny that. By the time she returned, Mark was awake holding his grandson who was once again screaming at the top of his tiny lungs. Lexie knew that Mark had limited patience when there was a screaming baby or child. Apparently he had found patience in the form of his newborn grandson. Lexie walked over to him and once again took the baby from his arms. Mark was getting frustrated. He didn't seem to be able to comfort his grandson. He really wasn't good with babies and he was starting to realize that maybe he needed parenting classes to help him get comfortable with parenting.

"I can't handle this." Mark told Lexie as she walked around the apartment, rocking the baby in her arms.

"Yes you can. You are a new father. A single father at that. It takes adjusting." Lexie assured him.

"You are going to help though right?" Mark asked nervously. Mark really didn't want to do this on his own. If he did this on his own, then he'd have a better chance of screwing up.

"Of course. I'm here to help you Mark." Lexie reassured him. Mark watched Lexie rock his grandson and he couldn't help but let a smile escape his lips. He loved watching her with his grandson. She looked so comfortable with a baby. She looked beautiful. Mark wondered how he had gotten so lucky to get her back.

"How did Karev take the news?" Mark asked. Lexie shrugged slightly so as not to disrupt the baby.

"He's okay. He claimed to know it was coming." Lexie told him. Alex hadn't been too surprised. Lexie suspected that he had just been waiting for the other shoe to drop metaphorically. Mark didn't really care how Alex had taken it. He was just glad that Lexie had ended it with him so that she could be with Mark.

"Karev doesn't always get the girl." Mark commented with a smug smile crossing his lips. Lexie shot him a disapproving glance. She really didn't want to see Mark be smug. That was not one of his most charming qualities. Mark stopped smiling smugly and just smiled apologetically at Lexie. Finally the baby had fallen back asleep in Lexie's arms with his little hands balled up under his chin. Lexie put him back in his crib as Mark came up behind her and pulled her body into his arms.

"I love you." Mark whispered against her hair. Mark knew that they had decided to start slowly but he couldn't help but want to be honest with Lexie. He loved her and he wanted to spend the rest of his life with this woman. Mark knew that she loved him too even if she wasn't ready to admit that to him just yet.

"Mark, we agreed to take it slowly." Lexie reminded him softly.

"Well maybe I changed my mind. Maybe I want the freedom to tell you how I feel without thinking that we'll screw things up by being honest." Mark told her. Lexie chewed on her lower lip wondering if maybe Mark was right. They had already gone through so much that maybe it was pointless to expect to be able to go back to the very beginning when she had asked him to teach her.

"Okay." Lexie whispered. Mark flashed her another quick smile and he brought his lips to hers. He had missed this with her. The ability to just grab her and kiss her whenever he wanted to. Of course now he had the added complication of a grandson but right now that baby was sleeping and Mark wanted to focus on kissing Lexie.

"I love you too." Lexie murmured between soft kisses. Mark was sure that life couldn't get much better than this. He had his grandson and he had Lexie.

Derek had been able to slip out of the hospital to go pick up his sisters and mother at the airport. He hadn't been able to call Mark since he had left his apartment hours ago and he hadn't heard from Mark. Derek figured that Mark was doing okay and that Lexie was likely still with him. Lexie was good for Mark. Derek had been one of the main people opposed to their relationship but Lexie made Mark happy and Derek wanted that for his best friend. He wanted Mark to feel the kind of love that Derek felt every day with Meredith.

Because of the latest security measures at the airport Derek could no longer go to the gate to meet his mother and oldest sister's plane. He decided to wait for them by the escalator. Amelia's plane would be coming in a little later so once he had Nancy and his mother, then they'd all wait for Amelia's plane. Derek had gotten there just as the plane from New York was unloading. He didn't understand why Nancy had flown in with his mother when Nancy lived in Connecticut, but he didn't dwell on that thought for long. Less than fifteen minutes later he found himself being hugged by his mother and then his sister.

"Where's the baby?" Carolyn asked as soon as she let go of Derek. Carolyn had hoped to see her surrogate son's grandson waiting with Derek. Did that make her surrogate great grandma? Carolyn wasn't sure what she was.

"Yeah I thought you'd bring him." Nancy complained. Nancy on the other hand couldn't think of herself as Mark's sister because she had slept with Mark on more than one occasion. That would make her not related to Mark's grandson in any way.

"You guys do realize that it's Mark's grandson right? Not my son or Mark's son." Derek reminded them.

"Yes Derek we realize that but where is he?" Nancy demanded.

"We finally got him to sleep so he's sleeping and so is Mark." Derek told them both. Both Nancy and Carolyn were disappointed but Derek knew that once they got to see the baby, their disappointment would be gone.

Apparently Amelia's flight had gotten in early. Only five minutes after Derek was reunited with his mother and Nancy, Amelia came flying down the escalator. Derek and Amelia's relationship had been very rocky for awhile and Derek was hoping that he and Amelia could use this time to mend fences.

"Amy isn't high, is she?" Derek asked his mother in a low whisper.

"I sure hope not." Carolyn whispered back. Carolyn hated that Amelia's addiction had caused such a rift between Amelia and Derek.

"If she is, I know Mark won't let her near the baby." Derek told his mother. Amelia heard the tail end of the conversation and she already looked hurt. Addiction was not a joke and she would be battling this all her life. She was healthy and happy right now.

"Derek do you really think I'd come to see the baby if I was high?" Amelia demanded as soon as she stepped off of the escalator.

"I hope not." Derek told her simply. Derek knew that Amelia had struggled with addiction but he had no sympathy for her.

"Because I wouldn't. I'm clean and sober as the day I was born Derek so stop with the accusations." Amelia informed him, clearly irritated with her brother. She turned to her mother and big sister and hugged them. She hadn't seen them since she had made the move from New York to Los Angeles.

"Where's the baby?" Amelia asked.

"He's finally asleep and so I didn't want to interrupt." Derek told Amelia.

"Does the baby have a name yet?" Amelia asked finally looking at Derek.

"Not unless Mark came up with one since I've been gone." Derek told Amelia.

"That poor kid has to have a name." Nancy agreed.

"I mean he's stuck with Mark as a single father. He doesn't even have a chance not to be screwed up." Amelia commented with a shake of her head. Both Carolyn and Derek shot Amelia a look. Carolyn believed Mark could do this and Derek wanted to believe that Mark could handle this on his own.

"Amelia, use that filter." Derek reminded her. Amelia was sick of everyone reminding her to filter her words. She was a grown woman and yet she had her former sister in law and her brother reminding her to filter the words that spilled out of her mouth. Amelia resisted the very strong urge to clobber her brother. She was an adult and she didn't want to start World War Three in the airport.

Finally Derek and his mother and sisters arrived at Mark's apartment and it was strangely quiet. Derek assumed that both Mark and the baby were sleeping. Maybe Lexie had left already. But Lexie had no way to get home because Derek had stranded her when he had gone off to work. Derek was grateful that Mark had given him a key because he needed to let his sisters and mother descend on the yet to be named baby boy soon or else they were going to drive him to the nuthouse. When Derek unlocked the door he saw Mark and Lexie together on the couch sound asleep. Derek flipped on the light and that woke Lexie and Mark up rather quickly.

"What the hell Derek?" Mark complained as she struggled to his feet. Lexie's pale skin flushed pink as though she was a teenager who'd been caught with her boyfriend.

"Nice welcome Marky." Nancy teased him. Mark shot a glare in Nancy's direction when he heard her words. God he hated that she called him Marky. That was her little nickname for him. It always made him feel as though he was five years old. Lexie was doing her best, attempting to smile at this situation when really all she wanted to do was crawl under a blanket and never come out. Derek's sisters were Mark's family as well and she felt rather intimidated by them.

"Lexie it's good to see you again dear." Carolyn greeted Lexie with a smile and a hug. Being hugged by Carolyn made Lexie relax almost instantly.

"So this is the sister of the infamous slutty intern." Amelia commented.

"She's not slutty Amy and she's not an intern anymore. She's a resident." Derek told Amelia with a look of exhaustion on his was sick of Meredith being called the slutty intern.

"Meredith's my half sister." Lexie told Amelia quietly. Not that Amelia deserved an explanation but Lexie felt like she needed to correct the youngest Shepherd sister.

"So Mark, where is he?" Carolyn asked, hoping both Nancy and Amelia would just shut up. The whole slutty intern thing was old and she was sick of it being rehashed by Nancy in particular.

"He's sleeping in my bedroom." Mark told Carolyn. Carolyn, Nancy and Amelia followed Mark into his bedroom to get a look at the sleeping baby. Lexie followed the group into Mark's bedroom but she stood back, suddenly feeling like an outsider. Derek had already slipped out the door, wanting desperately to get away from Amelia and Nancy and his mother.

Mark turned around and saw Lexie hanging out by the held out his hand and Lexie took it and went to his side. Mark wanted Lexie by him as much as possible. They had missed so much time together and Mark wanted desperately to make up for that.

"He's got your nose Mark." Carolyn whispered.

"That's the Sloan nose." Mark pointed out.

"Does your daughter have that too?" Carolyn asked.

"God I still can't believe you have a daughter Mark." Amelia commented with a shake of her head.

"I can. He hasn't exactly taken a vow of celibacy." Nancy pointed out.

"But he's got an endless supply of condoms." Amelia countered.

"Hey, I asked Mark a question. Let him answer." Carolyn told both sisters quickly before they could continue the conversation.

"Yeah she does." Mark answered Carolyn's question.

"She looks a lot like Mark." Lexie told everyone quietly.

"Do you have a picture of her?"Carolyn asked. Mark let go of Lexie to cross the room to his dresser. He pulled a silver frame off of the dresser and handed it to Carolyn. Amelia and Nancy looked over Carolyn's shoulder.

"She's beautiful Mark." Carolyn told him simply.

"No wonder she got knocked up." Nancy commented. Nancy had to admit that Mark and the nameless, faceless woman had made a beautiful woman together.

"If I wasn't completely straight…"Amelia trailed off suggestively.

"Amelia" Mark growled. That was his daughter and he really didn't need to hear what Amelia was likely thinking.

"That was taken at Derek's Christmas dinner last year." Lexie informed Nancy, Carolyn and Amelia softly.

Just then, the baby started to stir and before long he had erupted into a wail. Mark went to grab him, but Carolyn shooed him away.

"Go take a walk with Lexie." Carolyn told him.

"Sure you can handle this?" Mark asked a little uncertainly.

"I have 5 children and fourteen grandchildren. Fifteen if you count your daughter. Go." Carolyn assured Mark. Mark didn't want to argue and he trusted Carolyn. Nancy had six children so he trusted her as well. Amelia was a different subject altogether.

"Oh come on Mark I'm not going to hurt him." Amelia exclaimed when she caught Mark's uneasy glance.

"Okay, we're going." Mark told the three Shepherd women as he grabbed Lexie's hand and headed towards the door. Finally they were going to be able to get out of the apartment and have some time to themselves. Once they got into the hallway, Mark kissed Lexie softly as his hands tangled up in her hair. Lexie ruined the kiss when she started to giggle in the middle of it. Mark pulled away and smiled at her.

"Let's go."He told her,still smiling at her.

"Okay." Lexie told him simply. She loved him and she couldn't wait to spend time alone with him. They needed time alone together and Derek's mother and sisters had given them that gift.