"Sammy I got some good news!"

Both Sam and Cas looked up as Dean walked in looking down at his phone with a huge smile on his face. It had been a long time since Dean smiled his genuine smile. Sam leaned back from his laptop with a curious expression on his face.

"And that is? Good news doesn't happen with us much."

Dean nodded.

"So I heard from Ava and she agreed to come stay with us."

Sam's mouth dropped as he stood.

"What the hell did you do to get her to agree to that? Not that I'm not happy because i am ecstatic but she told us she wouldn't do that unless hell froze over."

Dean glanced at Cas who looked confused.

"I know hell hasn't frozen over Cas before you say it. Ava is our sister….half sister. She was Adam's twin. She's agreed to come stay with us."

Cas nodded. He knew well about Adam after calling him assbutt and lighting him on fire while he Michael's vessel. Cas didn't know much about Ava. She had distanced herself from her family for the most part which left Sam and Dean jumpy over her. The boys clearly had a better relationship with their sister than they did their younger brother.

Cas was pulled from his thoughts when Dean started speaking again.

"She should be here like 45 minutes."

Sam sat back down looking even more peaceful now. He and Dean had been begging Ava to come to be with them since John had died. They didn't trust their sister's safety with her college roommates. It would only be a matter of time before the things they hunted went after Ava .

Dean cheerfully went back to the beer in front of him and didn't say much until a knock on the bunker door made both himself and Sam jump. Sam quickly stood racing to the door followed by Dean. Sam gave his brother an excited smirk before opening the door.

Cas who hadn't moved from his spot glanced over to see Sam pull something small into his arms.

"SAMMY!"

Sam smiled eagerly hugging his sister tighter.

"Damn dude don't kill her. It's my turn."

Dean said taking the girl from his brother.

Upon being let go Ava who thought the life had literally been hugged out of her smiled at her two older brothers.

"Suprise! So just to throw it out there you all were right. I do need to be here with you both."

Cas blocked out the conversation going on feet away until he heard his name mentioned. He looked up as Dean said his name finally looking at the girl feeling like he had gotten struck by lightning. She was without a doubt the most beautiful thing Castiel had ever laid eyes on

"He does talk from time to time. Angels can be odd."

Dean said with a smirk earning a scowl from Cas.

"Hello"

He managed to get out looking back to the girl who looked remarkably like Dean. She had his hair color and the same green eyes except a few little differences. When she smiled it was Sam's smile. If Cas didn't know better he wouldn't have thought they were only half siblings.

"Hi."

Her voice was almost musical to him which left Cas in even more confusion. What was he feeling and why was he feeling this way? This wasn't a feeling he had ever had before. Was this what love felt like? If so he wanted more of it...but was it wise? Wise to love a girl you had just met and literally knew nothing about other than the fact she had the most precious smile? There was also the fact she was human and was young...very young.

Over the following weeks Ava got used to living with her brother's. They were in and out so it wasn't as if they were spending every waking moment together. She could live with that. Ava hadn't told them the real reason she was moving back. She wasn't ready to even admit that one to herself yet.

Then there was Castiel...Ava stopped stirring the pancake mix she was working on when the thought of the angel came into her mind. Within the past few weeks she had grown increasingly closer to him so close in fact that he was living in her dreams.

"I need to stop this."

Ava muttered. Falling in love with an angel probably wasn't too wise. He probably wouldn't even understand her feeling. If he did he wouldn't want some fragile human. Cas would want some beautiful angel girl that could give him anything he wanted.

Ava was so lost in her thoughts she hadn't even heard Castiel appear in the room. He stood watching her for a moment before looking at the clock on the stove that read 2:14 am.

"Are you alright?"

Ava jumped hearing his voice. She quickly turned to see Cas watching her with that adorable confused expression on his face.

"Cas you scared me. I didn't even hear you come in. Is everything alright?"

Cas nodded.

"Of course. Why are you up so late?"

Ava shrugged.

"Insomnia strikes again. You've been away for a while."

Cas nodded looking awkwardly down at the ground. How did he tell her that he had kept away so he was fawning over her? How did he tell a girl who was literally thousands of years younger than him that he wanted her? Most importantly how did he tell her about a war in heaven and even if they did get together it would be hard?

"A lot of angel stuff going on."

He replied as Ava walked to the couch patting the place next to her.

"Come keep me company. Sam and Dean won't be awake until noon. They haven't been in bed long."

Cas walked over taking off his trench coat before sitting down. The two sat in silence for awhile watching boring late night movies.

"You look exhausted."

Cas said softly. Ava nodded.

"This insomnia is awful. I've had it since Adam and my mom died. The nightmares are awful."

"You watched them die didn't you?"

Cas asked slowly slipping his hand around hers and to his shock she squeezed back.

"I did."

They remained quiet for a few moments with Ava periodically stroking her thumb over his knuckles.

"I can help you sleep you know."

Cas suggested silently hoping he wasn't going to push her away or make her think he was coming on too strong. He wasn't ready to admit to her that he had spent the past few days observing humans in relationships and their behaviors. If she would accept him he wanted to know how to act.

"Ok."

Ava replied feeling more than willing to try whatever the angel had up his sleeve for a sleeping trick. Cas slowly turned her in his arms so she was laying with her head on his chest. She could clearly hear his heart beating and for the first time in a long time she felt peace.

Cas slowly placed his index finger and middle finger on her forehead slowly lulling her off to a peaceful sleep. As her eyes closed and she nestled against him Cas watched her with love filled eyes. At this moment he was almost positive that he had formed a union with her. Human or not he would love her and keep her safe. He would find a way to keep her young and not let her die.

At the same time he was scared. He had seen his brothers find their soulmates only for it to not last. Would Ava tire of him and his not so human ways? What if his lack of people skills and lack of knowing how to be a good lover was a deal breaker? Cas didn't want to pour his soul out only for it to be crushed.

Cas sighed stroking a hand through her curls. He couldn't stay away though. There was no way he could. The connection was too strong to break. Ava's soul called to him in a way that no other had in the years he had been in existence. But he was worried...worried about his enemies that would possibly hurt Ava to get to him...it could be a disaster.

Slowly he leaned down pressing a soft kiss to her forehead. Ava sighed happily still not letting go of his hand.

"Ava?"

"Hmm?"

She said in between a yawn and a nuzzle to his chest. Cas couldn't fight it….not at this moment. The next day he would talk to Sam and Dean to get their permission before he made a romantic move on a more conscious Ava.

He gently brushed her dirty blonde curls away from her face before whispering in her ear.

"May I keep you?"

Ava smiled squeezing his hand before clearly falling into a deep peaceful sleep.