Background: Ryan is thirty years old and has a five-year-old son named Devlin who he had with Jenny. Jenny died when Devlin was two from a stroke, leaving just Ryan trying to care for their child.

Author Notes: I tried really hard to get the timeline straight on this story but if there are discrepancies I apologize. It's not set in any particular season. Also there are a few small holes in the story but just bear with me. I don't own any Castle characters.

Feedback is appreciated and happy reading!

After a long day at the precinct Ryan knocked on the door next to his apartment and smiled when an elderly Spanish woman swung it open and smiled brightly. "Hello señor Ryan." She turned and shouted into the apartment, "Chico." A small boy ran over and Ryan dropped down to hug him.

"Hey bud, ready to go home?"

The little boy nodded and the two turned to leave but paused when the woman asked, "Señor Ryan? A word?"

He nodded and gently shoved his son towards their apartment with the house key. "Yes?" he asked distractedly as he watched his little boy enter the apartment.

She clasped her hands together and bit her lip. "My son called me today and he needs some help back home. At the end of the week I will be returning to Mexico. I can no longer care for Chico."

Ryan looked shocked. "Oh, uh yeah. Alright. Is everything ok with your son?"

"Oh yes, he just needs help señor. I'm sorry it's short notice."

He waved her off, "No, its fine. Thank you for everything you've done. I couldn't have done the last few years without you."

She smiled warmly and cupped his cheek in a motherly fashion, "God watches over his children and gives them what they need. I have a feeling what you need will come along very soon señor."

Ryan smiled at her statement and nodded, "Have a good night."

Two days later Ryan sat at Castle's poker table with Beckett, Castle, and Esposito. Everyone was doing well except Ryan who seemed to be spaced out the entire evening. When he spoke his words sounded distant and he was making rookie mistakes as the game progressed.

"….. and then a teenage mutant turtle jumped off a helicopter and broke out an ice cream party," he heard Castle say.

Ryan shook his head, "They'd come from the sewer and it'd be pizza." He glared at larger man, "I'm listening to everything, I'm just preoccupied."

"With…" Esposito asked as he threw a few chips into the center of the table.

Ryan sighed and rubbed his hands up and down his face after throwing down his cards and just giving up, "Claudia, my neighbor who watches Dev, is leaving in two days and I can't find anybody I trust to watch him. I have no idea what I'm going to do."

Everyone quieted as they all racked their brains trying to come up with a solution. No one really had a lot of family that lived locally, and the family that did was too old to care for a child almost daily. Beckett opened her mouth but Ryan shook his head, "I'm not putting that on your dad but thanks. Claudia had a hard enough time trying to keep up with him, I need to find someone younger."

Castle nodded, "We'll figure something out. I can babysit until you do find someone." Seeing Ryan's expression he sat up straighter, "I know I don't do or take very many things seriously but I did raise a child and I am quite energetic. It'll at least take the pressure off finding someone within two days."

Ryan bit his lip, "I don't want you to feel like you have too. He's not super busy but he's definitely a handful."

"What five year old isn't?" Castle countered. "No stress, just think about it and let me know. I wouldn't have offered if I didn't want to do it."

"Right, ok," he finally relented.

A question was eating at Castle and he hoped he wasn't overstepping a line when he finally asked it. "Ryan?"

"Hmmm?"

"Why have I never met your son, other than at the funeral? I've known you for over three years now," he asked cautiously and fought a flinch when Esposito looked up and fixed him with a hard stare.

"Beckett and I have. I see Dev quite a bit."

Ryan gently kicked Esposito in a silent warning, he appreciated his partner protecting him but he could handle himself. "After Jenny died Dev didn't do very well for a long time. I tried to limit his contact with everyone until he could even himself out more, I didn't want to force him to do things. Claudia and school helped quite a bit and he's finally back to where he should be. It's not anything personal against you."

Castle shook his head, "No, no I understand. You do what you have to for your kids, I get it." He smiled brightly, "I'm excited to finally meet him."

Two days later Ryan and Devlin stood in front of Castle's door and knocked.

The door swung open and Alexis smiled cheerily, "Hey Detective Ryan! How are you?"

He faltered for a moment at the unexpected person until he returned the smile, "Not bad. On break from college?" He was having trouble not staring at how absolutely beautiful Alexis looked. All traces of the little girl that left for college were gone and in her place was a woman with beautiful green eyes, killer smile, and long red hair.

"Actually I graduated last month. I'm home permanently now. What brings you here this morning?" It was then she realized that the man in front of her was not alone. She saw a small hand clutched in his larger one and as she peered around Ryan's legs she saw a small boy. "Who is this?"

Ryan gently nudged his son forward and placed his hands on his shoulders, "This is my son Devlin." Alexis had to stifle a gasp at how absolutely beautiful the child in front of her was. Wavy blond hair fell gently across his head and forehead and sat just above the most beautiful blue eyes. A small nose, pouty lips, and rosy cheeks sat perfect with his porcelain skin.

She smiled and bent down to his level, "Hi Devlin, I'm Alexis. It's nice to meet you."

The boy stayed quiet until Ryan gently squeezed his shoulder, "It's nice to meet you Alexis."

After she stood back up Ryan answered her question, "Castle is actually taking care of Dev while I find somebody to watch him permanently." Her eyebrows rose and she stepped aside so they could enter.

"Really?"

Castle appeared suddenly with a huge smile, "Yes really." He took in the boys appearance and shook his head, "God he's a beautiful child." Not wanting to make him uncomfortable he dropped down and grinned, "Hey Devlin, I'm Castle and we are going to have so much fun today. Let's start with pancakes and cartoons."

Devlin shifted and looked like he wanted to say yes but looked up at his dad instead. Ryan smiled encouragingly, "Its ok bud, go have fun." The boy smiled and after grasping Castle's hand followed the large man to the kitchen.

The two remaining people watched them until Alexis turned and quietly stated, "Nobody told me you had a son."

Hearing the obvious question Ryan adopted a strained expression and stuck his hands in his pockets. "Shortly after Jenny and I got married we had Dev. Three years ago she had a stroke out of the blue. It's just been me and Devlin since then."

Alexis nodded sadly, "I'm so sorry Detective, Jenny was a really special person. I only got to meet her a few times but I'll never forget her."

"Thanks." He forced away his rising emotions with a cough, "My neighbor has been taking care of Dev but she's moving so Castle said he'd babysit until I find a full time nanny."

"What about me?"

Confusion appeared on his face, "What about you?"

Realizing she was jumping ahead she smiled, "What if I watch him for you, full time?"

Ryan frowned, "You know about watching kids?"

"Well, no but I'm a really fast learner and I'd like to think I'm pretty responsible. I've been looking for a job while I take some time off and this would be perfect."

Castle, who had been listening in while he watched Devlin at the table chimed in, "Trustworthy too."

Ryan looked apprehensive so she tried to ease his fears, "If you say no it won't hurt my feelings. I'll just hang out here at the house and maybe if Dev likes me we could try it."

Ryan nodded slowly, "Alright. I have to go now though, I'm going to be late." He walked over to the table and kneeled down. "I'll see you later ok bud? You need anything you call me."

Devlin nodded happily as he stuffed another bite of chocolate chip pancake into his mouth, "Ok daddy, love you."

"I love you too and don't talk with your mouth full." He ran his fingers through the boy's hair and licked his thumb before rubbing some syrup off his cheek. "I know you already miss Claudia and that this is different but everything's going to be fine."

Castle watched with a sad smile, he knew what it was like to raise a child almost on your own. He knew how emotionally draining it could be and how difficult it was to place the most precious object in your universe in the care of someone else.

Ryan finally stood and walked to the door, Castle clapping him on the back as he led him out. "Don't worry about anything. One dad to another I will take care of him."

He relaxed slightly and smiled up at the other man, "Thanks Castle."

Many hours later Ryan knocked on the door and smiled anxiously at Castle, "How'd it go?"

Castle waved him inside and shut the door, "Why don't you see for yourself?" The two men walked to the living room where Alexis was reading quietly to Devlin who was curled up by her side listening intently. "We had a good day, very busy. Alexis thought we should get him calmed down since it's getting late though. She did really well with him today."

Ryan tilted his head as he took in the scene, "Huh. Oh, before I forget Beckett wants you to call her, she wanted your opinion about a few things with the case."

Devlin looked up at his father's voice and smiled happily, "Hi daddy."

Ryan held out his arms and the boy ran over and into his embrace. He picked him up and Castle had to stifle a laugh at how large the little boy looked in Ryan's arms, to the other mans credit though he never even blinked at the weight or size. Castle couldn't exactly remember how large Alexis was at five years old but Devlin seemed small to him, but that was also might have something to do with the fact that his parents were 5' 1" and 5' 8".

Devlin wrapped his arms around his dad's neck and buried his face in his neck, "I'm tired."

"I know we're going home." He walked to the door and turned, "Thanks for everything Castle, you too Alexis. We'll be back in the morning."