A/N

Hi there!

I had this idea in my head or a long time and finally I decided to write it down and upload here :)

Hope you'll enjoy it.

And, as english is not my mother tongue, please, be gentle :)

Three years.

It's been three years since they started being a couple. And two, since they got married. Their life was as peaceful as it could be, when it comes to them. Everything was fine between them, between their whole family.

However, there was that little something, what was poisoning their little bubble. Castle remembered too clearly how devastated Kate was, when six months ago, after a miscarriage and some tests, her doctor said that she won't be able to have a child. It took some time for her to finally somehow accept it. They moved on, she moved on, starting to think about some other way to have another kid. And though Kate was still upset with the thought of being unable to have a child, all she wanted now was to be happy with Castle.

So she did, they both did. She was doing her job the best she could, and Rick kept shadowing her. He published two more books, and was about to write another one.

So, they could definitely say, everything was fine.

And it was so until that one day in June. Kate was waiting for Castle in the park near the precinct on her lunch brake. Today was a lazy day, no case, just paperwork, so her husband decided to stay home and do some writing. However, she got a call from him about a midday, when he announced that he need a brake and they decided to meet in the park. Detective was sitting on one bench, having a bag of crackers, looking casually around to see her husband. She had no idea, that she was watched.

Two pairs of eyes were observing her every move.

'Remember … be soundless' a nine-year-old boy whispered to the girl in his age.

She only nodded and made her way to the woman. Brunette haven't noticed her yet, so she reached carefully for the paper bag, biting her bottom lip.

'I wouldn't do this, if I were you …' soft, quiet voice made her froze.

Girl raised her sight from the bag to the woman nearby. She wasn't angry, as the little thief expected her to be, but have a light smile on her face instead. The woman looked her up and down, frowning a little.

'You're hungry?' she asked, but before girl could answer, the boy jumped out of his hiding and run to her.

'Let's go!' he hissed and grabbed her wrist.

But before they managed to run away, Kate stood up, and caught their shoulders.

'Not so fast, guys' now she was fully serious, but when the kids started to struggle, she added. 'Hey, clam down you two. I won't do anything to you, ok?'

They calmed a bit, but the boy was still looking at Kate suspiciously.

'You're here together?' detective asked, crouching down to be on children's level. As they nodded, she continued. 'Judging from the fact that you wanted to steal my crackers I assume you're both hungry, right?'

Kids exchange quick looks and nodded once again. Detective smiled.

'Ok. Now, I'm detective Kate Beckett. Can you tell me, what are you doing here alone? Where are your parents or anyone who's taking care of you?'

'No one is taking care of us' said the boy proudly. 'We can take care of ourselves!'

Kate chuckled.

'Yeah, I see … but, seriously … is there any adult responsible for you?'

They shook their heads.

'No …'

The woman looked the kids up and down. Orphanages, she thought immediately. She felt her heart aching, as her sight was examining two 9-year-olds in front of her. How pitifully they looked, scrawny, in their scratchy clothes. She couldn't left them like this.

'Come with me …'

Meet me at Remmy's. Explain later. LY.

That was the text he got from Kate just as he was about to enter the park. He frowned. What makes her change the place so suddenly? Feeling the sting of fear, he hurried to Remmy's. Lucky for him, it wasn't far away, so few minutes later he opened the door, just to see his wife sitting by the table, with two kids, who were devouring their meals. He froze in one moment, stunned.

'Kate? …'

She turned her head to him, so did the kids.

'It's all right, guys' she said to them, and then, she smiled to Castle. 'Come here, Rick.' and as he reached their table, she forced him gently to sit next to her. 'Kids, meet my husband, Richard Castle. Rick, this is Nick and Nicole.'

Then, she explains all this situation to him, and as soon as writer heard whole story, a bright smile, appeared on his face. Twins were finishing their meal, and now, they were looking hesitantly at the adults.

'So …' Rick started. 'What we're gonna do with you? …'

'You don't have to do anything' said Nick. 'We're …'

He was cut off by a subtle ringing, announcing someones appearance. Twins eyes widened as they saw a man who just entered the building. He was quite tall, but thin, in his thirties. His dark hair were contrasting with pale skin and cold-blue eyes. It was too late to hide. Castle and Beckett saw how the children's behavior changed, as the man came closer to their table.

'There you are, little ones!' he said. 'I was looking for you everywhere!' then he turned to Kate and Rick. 'I'm sorry … they run away from me again … but now we're coming home' he reached for Nicole's arm.

'Leave her!' Nick jumped up, just to pull his sister closer to him.

'Excuse me, sir' Kate interrupted, standing between the man and children, seeing by the corner of her eye, that Rick did the same. 'Kate Beckett, NYPD. May I ask, who are you?'

'I'm .. I'm this kids uncle. I'm taking care of them' he said.

'He's lying!' yelled Nick. 'We don't know who he is!'

'He's been following us for some time' added Nicole 'Please … don't let him take us …'

The man laughed.

'Silly ones … but enough of this game, let's go home …'

'Not so fast' Kate gently pushed him away from children, as the man wanted to reach for twins anyway. 'These kids are under witness protection. So I'm sorry, but you can't take them anywhere.'

That was a lie, but it was obvious for Kate, that she couldn't let this man to take twins. She didn't know why, but now she felt somehow responsible for them. She saw his jaw tighten, but soon he smiled softly.

'But detective, I really can take care of them. And witness protection? Why?' he asked, trying to act like he was really surprised.

'I can't tell you the details, but those kids are important witnesses, and they have to stay under my security' Kate crossed her arm on her chest.

'Bullshit!' he hissed, and was about to pulled Kate away, but then, Rick appeared just by her side.

'Touch my by one finger, and you'll end up in my custody for assaulting a police officer' she said calmly.

'And I'll be a very reliable witness, just as the kids. So, it will be better if you just go away.' added Rick.

Thirty-year-old stared at Rick for a moment, then he looked at Kate, at twins and a few seconds later he snorted and turned on his heel to walk away.

'We have to go' mumbled Nick, taking Nicole's hand. 'Come, sis.'

'Yeah, sure' Kate smirked. 'Go and let that man catch you.'

The girl looked at her brother. They knew she was right. In the same time, Kate exchange sights with her husband. Castle know exactly what Beckett wanted. And to be honest, he wanted the same now.

'Listen, here's what we can do' said Rick softly. 'You can go with us, and let us take care of you. And if you'll tell us about that guy, maybe we'll be able to help you. So?'

Sibling looked at each other once again, and though Nick wasn't very pleased with that, Nicole seemed relieved.

'We agree. Please, help us …' they answered in unison.