Disclaimer in Chapter 1.

Rick was well and truly flustered as he went through the never-forgotten habit of changing his daughter's diaper. That Kate was here stunned him, after the way she left it at the station, asking for time, obviously unsure and a little afraid. He'd worried that she wasn't ever going to think he – they – were worth the chance.

But she was here and she was teasing him, flirting with him… he hadn't missed the way her eyes wandered over his chest again and again. She'd called him extraordinary! Hell, she'd called him Rick.

Something had finally changed for her. It was like something had unlocked itself and let her open up to him, in a new way.

He'd always known that she was confident, sexy and fun… but that she hid her true self behind alternating layers of kick-ass and badass… so that she could do her job and be 'Detective Beckett'. He understood that, he loved that about her, but what he had just seen was truly just Kate and he'd been waiting for that for a very long time.

He'd just witnessed was the first sign of her accepting that they were going to be great together and that she was ready to find out just how great.

He just didn't want to smell of spit-up when they did.

He looked down at the gurgling baby on the changing mat and realised he'd changed, wiped and re-dressed her without even thinking about his actions. It was a pity that he couldn't say the same for himself. He needed to shower and change. Looking over at the crib by his bed, he knew that Sophie would be sleepy after her bottle, but just like with Alexis, the overly protective part of him hated leaving her alone in a room when no-one else was home…

He grinned.

Yes, that was a much better idea.

He knew that a big part of Kate's issues has stemmed from Sophie. He had even understood why. At first it was because she knew that CPS were going to get involved, after all, he'd seen Ryan and Esposito step back from that as well. They were cops through and though and as such they understood the dangers of getting emotionally involved, so they protected themselves as best as they could from it.

But it was later, once the adoption process had begun, as Ryan and Esposito, hell, even the Captain had almost come to blows right in the middle of the station about who got to hold Sophie that Rick had realised Kate was still holding herself back. That she barely looked at his little girl, let alone asked to hold her, or touch her. If it had been any other woman, Rick would have been hurt badly by that, but it wasn't any other woman. It was Kate, his Kate and he knew her better than she ever suspected.

As amazingly great at her job as she was, as perceptive and insightful as she was when it came to murders and as compassionate and generous as she was with the families left behind by those acts of violence, when it came to herself, Kate Beckett was an idiot. Because the more she felt, the more she had the potential to feel, the closer she guarded her heart.

But Rick knew that this wasn't just about her protecting herself.

No, the central plot in this little story he was living through was that Kate Beckett was trying to protect him.

She was trying to protect him and his family.

"Ah, Sophie, she can really be dumb sometimes, can't she? It's a good job we love her, isn't it?"

Rick picked up the little girl and stroked her nose.

"I think it's about time that Kate Beckett got to see just how irresistible us Castle's can be."

Kate spun away from the photo she was examining when she heard him pad back into the living area. He carried a freshly changed and fist-sucking baby in one arm, while he was attempting to force his hair into some semblance of order with the other.

He was still half naked.

She couldn't decide if that boded ill or well.

Watching his shoulder flex, she decided well; very, very well.

But it surprised her. "I thought you'd gone to change?"

He smiled at her, that devil-twinkle in his eyes making an appearance. "I did, but she's sleepy and I don't want the shower to wake her. Come here…"

Kate automatically took a step towards him and before she really knew what was happening, he had pulled her arm up and gently placed the sleepy baby in the crook of her elbow. Her natural instinct took over and she curved both arms around the warm weight while her heart stuttered at the sensation.

Her eyes caught his and just for a moment she saw a purity of joy flash deep across his face before he took a step back.

"Great, just rock her for a minute while I shower?" He smirked at her and started to walk away, turning his back before she had a chance to protest. He didn't even stop walking when he called back over his shoulder. "Thanks, Kate."

She watched his retreating back a moment longer, thinking he had a nerve calling his mother 'Hurricane Martha' as she had just been witness to 'Hurricane Castle'. Before she could dwell on that any more, Sophie snuffled in her arms and Kate automatically snuggled her deeper into the protection of her hold.

And she smiled.

A deep, soul affirming smile because for the first time since she had realised in the bullpen just what Castle had planned to do, she wasn't afraid of this little girl and what she represented.

Rick leant against the closed door and took a deep breath.

That had been a gamble.

Sure, he'd played it off as deliberately nonchalant, but he'd known exactly what he was asking of Kate.

But he also knew he had to push, just a little, because regardless of Kate's intent for coming here this evening, he had to be absolutely sure that Sophie wasn't going to be the deal-breaker for them.

He let out the breath he'd pretended not to have been holding. Kate could quite easily have panicked and the push he'd just given her would have been too much. But he'd watched her eyes soften as she held his little girl safe in her arms and it was enough for now to make him hope for the future he'd been wanting for a very long time indeed.

A moment later, his breath stopped once more. He stood frozen to the spot while his heart tried to beat right out of his chest.

Because he had just heard Kate Beckett start to sing a lullaby to his daughter.

TBC…

AN: Wow, you guys, your reviews are amazing! Thank you so much!

Chapter 11 will be up tomorrow. I promise.