Disclaimer: I don't own anything.

Author's Note: I started this story a few months ago and originally planned not to upload it, but then I thought maybe there are people a few people out there that might actually enjoy it, so here I am, uploading it. If you happen to find any grammatical errors or spelling mistakes, please point them out to me. Thank you!

Chapter 1

"Daddy!"

Richard Castle barely caught his balance as his redheaded whirlwind of a daughter flung herself at him.

"Hey there, Pumpkin," he chuckled, hugging her to him. "How was school?"

"We learned all about the night sky today. It was so fascinating!", the little girl told him with bright blue eyes. "And I made a new friend. He is only in first grade and really, really shy. I met him at recess," she continued without taking a breath. "He was all by himself and looked so sad, so I went to talk to him and it turns out, he is really funny once you get him to talk to you. Do you want to meet him? His mom hasn't picked him up yet. Come on!" Without waiting for a reply, the 8-year old impatiently grabbed her father's hand and pulled him back through the school entrance towards the sturdy brick building.

Castle let himself be dragged along and laughed quietly at his daughter's behavior. At moments like these he saw a lot of himself in her.

He let her pull him to the corner of the school building, towards a dark-haired boy, who sat on the ground, looking thoroughly forlorn.

"Hi Louis, this is my dad," Alexis started the introductions. "Daddy, this is Louis, my new friend," and on a whisper she reminded him, "He is really shy".

Castle squatted down to be at eye level with the boy. "Hi Louis, I'm Rick."

When the boy looked at him, Castle was met with two large, chocolate brown eyes and a small, hesitant smile.

Not knowing how to react to the boy's silence, Castle tried to coax him out of his shell. "I heard you just started school this fall. How do you like it so far?"

"It's alright," the boy stated vaguely, picking at something on the ground.

"Are you learning lots of cool stuff?" Castle tried again.

"I guess."

"He told me, he already knows how to read. And he's only in first grade!" Alexis told her dad, proud of her new friend.

"You knew how to read before you first went to school," Castle reminded her. "In fact, you were only five years old."

"Yeah, but you are a writer, daddy, I'm supposed to know how to read and write before I start school." Alexis gave him her 'silly you look' and Castle playfully struck his tongue out at her, making her giggle.

"So, what does your mother do for a living, Louis?" Castle wanted to know, still trying to get a conversation started with the boy.

But before Louis got round to answering his question, Castle caught sight of a woman in a grey pantsuit and shoulder-length curls walking toward them hurriedly, car keys jingling in her hand.

"Louis, baby, I'm so sorry! I'm so sorry I'm late!", she called, almost jogging now - in incredibly high heels as Castle noted with an arched eyebrow.

At the sound of woman's voice, Louis quickly scrambled to his feet and met her halfway. He threw his arms around her middle, pushing the front of her blazer out of the way, giving Castle an undisturbed look at the police badge, that was clipped to her belt.

"Your mom is a cop?!" he asked, childlike amazement written all over his face.

"And you are?" the woman replied, looking him suspiciously up and down while hugging her son protectively into her side.

"I-I'm Richard Castle, my daughter Alexis is friends with your son," Castle explained and pointed at the little redhead, who had decided it was her turn to be shy now. She hid halfway behind her father and gave the tall brunette in front of her a quick wave.

The woman seemed relieved by that and gave the Castle's a warm smile. "I'm glad to hear that. I'm Kate by the way."

Castle shook her extended hand, but before he could start a conversation, Kate looked down at her watch and then gave him an apologizing look. "It was nice meeting you, but we really need to get going." With that, Kate took Louis' hand and quickly led him out of the schoolyard.

Castle mirrored her actions and slowly began the walk home with his daughter by his side.

"She was so pretty!" Alexis exclaimed after a couple of minutes of walking in silence, astonishment sparkling in her bright blue eyes as she looked up at her father.

"She was," Castle agreed. "We should invite them over for a play date sometime soon."

"Are you saying that because you want me to have someone to play with or because she is a cop and you want to ask her all kinds of weird questions for your next book?" Alexis narrowed her eyes at him in suspicion before grinning widely. She knew her father just a little too well.

"What makes you think that? I'd never!" Castle replied with mock hurt, grasping at his chest in an overly dramatic gesture that his mother, a broadway actress, would have been proud of.

"You totally scared away Lizzie's mom with your questions about undetectable poisons. Lizzie isn't even allowed to sit next to me anymore in class!"

"You know I'm sorry about that. I just didn't know anyone else who has a major in chemistry and would know that kind of stuff," Castle explained, a little frustrated. He really hadn't thought that an innocent question like that would get him into so much trouble. For weeks, all the parents from his daughter's school had avoided him like the plague and warned their children about playing with Alexis.

"Just don't scare Louis' mom away," Alexis huffed. "Louis is really nice."

"Hey, I'm the cool dad, remember?" he grinned at her, winking playfully but Alexis simply giggled and he didn't know whether to take that as confirmation or not. But he was the cool dad, really!

XXX

At the same time, Kate slipped behind the steering wheel of her Crown Victoria and took a few calming breaths. She just met Richard Castle, her favorite author of all times! At her son's school of all places! She took a quick glance in the rearview mirror and groaned inwardly when she saw the bags under her eyes and her disheveled hair.

Not only had she not known what to say to him and fled from the school like an idiot, she also looked like she hadn't slept properly in days - which, unfortunately, was true.

No matter how tired or exhausted she was, she simply had a hard time falling asleep at night. The guilt ate her up alive. The guilt she always felt when she wasn't home in time for dinner, when she wasn't home to put her son to bed, when she was late again picking him up from school because, much like today, she lost track of time trying to figure out the puzzle on the murder board in front of her.

Being a single mom to a 6-year old and a Detective with the NYPD was harder than she had ever imagined it being.

Sighing, she started the car and pulled away from the curb. She needed to drop her son off at home, where his nanny was waiting, before going back to work.

"So, tell me about Alexis," she asked. "Did the two of you play together?"

"We just talked," Louis told her, looking out of the window. Kate was glad to hear that. She knew how shy Louis was, especially around strangers, and how hard it was for him to open up and engage with other children his age.

"What did you talk about?"

"Mostly school. She is in third grade and knows all about the night sky. She told me about constellations that are shaped like animals. Is that true, mommy? Do they exist?"

"I don't know, but we could go to the planetarium this weekend and take a look at all the constellations and find out. Would you like that?"

Louis gave her one of his rare smiles and nodded shyly.

"Alright then," she smiled back at him. "It's settled. We're going to the planetarium on Saturday."