Epilogue:

Kate carefully climbs down from the ladder to take a proper look at the banner hanging from each end of the wall, and when she sees that it's perfectly straight and aligned, a smile begins to stretch across her face.

"Finally got it right, huh?"

She turns, a brow arching as Castle comes up behind her, his arms wrapping around her waist and his chin resting on top of her shoulder.

Her smile only grows wider, hands placing atop of his against her waist as she turns her head back to the birthday banner draping over the living room, and leans her head against the side of Castle's.

A full year had gone by in the blink of an eye. Too much had happened, and Kate was still trying to process everything that had gone on.

Six months after Joseph was born, when she'd officially gone back to work – her desk had been taken over by a newbie, and she'd gone to grab all her stuff from a box in storage. But once she started to set her desk back up, she had ended up knocking over the family of elephants and it had shattered onto the precinct floor.

Still full of hormones, she'd almost broken-down crying – but the black tape in her line of sight had pulled her from getting emotional over her mother's belonging, and instead curiosity had coursed through her.

The tape had changed everything. On it – the man who'd murdered her mother; William Bracken. She'd had the pleasure of being the arresting officer, with Castle just mere meters away watching her proudly.

But, there was also another man on the tape – her Captain, and the pain that had inflicted upon her from his betrayal had almost caused her to quit her job right then and there. It took her months to even look at him – to even be in the same room as him and forgive him, but she got there eventually; could understand why he'd lied to her, why he had kept things a secret from her.

Finding her mother's killer and getting the justice she so desperately wanted hadn't been something Kate thought she'd ever get, but she got it. And something inside of her changed. The high walls surrounding her had been torn down, and the dimmed lights inside of her had been replaced with the purest beams of light – of course, Castle and her son had both helped with her coming to terms over the end of the case that'd made her who she was.

She wasn't afraid of who she would be without it – or how she'd go on without her mother's case right at her side, because she had so much more to keep her grounded and full of life now.

"Yeah, after no help from you." She smirks, lightly digging her head into Castle's more.

"Hey, I offered my assistance! You told me to go pick up the cake." He quipped, and Kate rolled her eyes, pulling back from her partner as she turned around to face him.

"Yeah, after almost fighting tooth and nail with you to go get it. Speaking of which, where is it?" Her brow raises, eyes roaming over the writer.

"Put it in the kitchen. You've got to see it, it's so adorable." He grabs a hold of her wrist, a wide grin plastered across his face as he pulls her into the kitchen before he's carefully lifting the white box open to reveal a grey elephant cake with the words Happy 1st Birthday on it.

There's no stopping the grin that spreads across Kate's face as her hands come to her chin while she gazes down at the cake. "Oh, he's gonna love it, Castle!" She leans across, pressing her lips against his cheek before taking a glance at the time on the oven and her eyes quickly widen. "Crap, people should be arriving soon. I better go get Joseph up and dressed." She lets go of Castle, quickly moving around the kitchen island as she heads towards the stairs.

"Did you lay out his birthday suit like I asked?" She asks, glancing over her shoulder.

"I really wish you wouldn't call it that, Kate." Castle's face scrunches, before a breath of air escapes as she rolls her eyes. "But, yes, I did." She sees the gleam in his eye and the bopping of his adams apple but merely shrugs it off as she continues up the stairs.

Slowly she pushes open the door to Joseph's nursery, carefully switching on the light as she sees the almost one year old standing at the edge of his crib, tiny hands wrapped around the bars and a binky in his mouth that's soon falling onto the mattress of his crib as he spots his mother, a wide grin plastering across his face as he gurgles at her.

Kate's heart can't help but burst. Every time she saw him, her entire face lit up and her heart filled with so much joy. She never knew it was possible to love a human being as much as she loved Castle and her parents, but then Joseph had come along – and she could finally understand the love a parent had for their child.

"Hey, baby boy!" She coos, quickly moving through the room towards him as he bounces up and down, falling onto his bottom and giggling. She can't help but grin even wider as she carefully reaches down into the crib and lifts him up. "Oh, did you have a good nap, hmm?" She presses her lips against his cheek, letting them linger there for a moment before she's hoisting him onto her hip.

Her fingertips carefully run through the boy's soft brown hair as his hands grip and grab at her shirt.

"Are you ready for your party, huh? You're going to be spoiled rotten today." She lightly tickles his tummy, watching as his face fills with joy, the bright blue eyes resembling his father's staring up at her before he's burying himself into her chest and she can't help but squeeze him tightly before she spins around and heads towards the changing table where she'd told Castle to lay out his clothes.

"Let's get you dressed and rea-" She comes to a complete stop, the smile on her face dropping and her heart beginning to thump rapidly beneath the cage of her ribs as she stares down at the black onesie with white writing across it. Kate's eyes can't help but fill with tears, her chest beginning to rise and fall as a lump forms in the middle of her throat.

She hears a clear of a throat behind her and quickly spins round, her grip on Joseph tightening as she stares over at Castle in the doorway.

"Wh – what?" She lets out a little breathlessly as she blinks a few times, a few stray tears slipping and falling down her cheeks as she swallows the lump in her throat.

The writing on the onesie, for a second, she thought she was seeing things, but the longer she stared at it, the clearer it was to her that she wasn't seeing things, that Mommy, will you marry daddy? Was indeed written across it.

Castle moves through the room, stopping just before Kate and Joseph before he eases himself down onto one knee and reaches out, holding his hand open for her and Kate moves the hand holding onto Joseph's leg to rest it in Castle's palm.

Her hand is shaking and he quickly grips it and her eyes fall closed, tongue dipping out of her mouth to run along her lower lip.

"Kate…" Her eyes quickly open, gaze falling to the deep blue eyes staring back at her.

"This past year with you has been everything and more. Our little family means so much to me, and I know that it took us awhile for us to come together."

Another lump forms in her throat as she thinks back to when she'd found out she was pregnant with Joseph, how she'd kept it from Castle after he'd left – how it had taken them awhile to get onto solid ground and reveal their true feelings for one another.

But the past year with Castle had been everything and more to her as well. They'd grown so much closer, fallen more in love with one another. She'd moved into the loft permanently and sold her apartment when Joseph had only been four months old. Because to both of them, it seemed silly for either of them to be living in separate places when they were together, and didn't want to be apart. Although Kate hadn't even slept in her apartment since before Castle had brought her to stay after that fateful case.

They were a family, they were partners – and keeping themselves apart any more seemed stupid.

"But I wouldn't change anything. I mean, maybe getting to this point a little faster with fewer obstacles." He quips, shrugging, and a bubble of laughter can't help but escape through Kate's lips. "I know that no matter what happens, you've got my back. That wherever we go, it's you I want by my side, and it's your side I always want to be by."

He squeezes her hand, his thumb running over her knuckles as he keeps his gaze locked on her.

"I never thought I'd write again, that nothing could live up to the books I'd written. But then you walked through that door… and my entire life changed. I'd never met anyone as extraordinary as you, Kate. Never met someone so stubborn, driven and strong. From day one I knew – I knew that you were so special – that you'd always be special to me, and not having you in my life, not having Joseph – that's not one I want to be in or be a part of. Because without you, my life is unfulfilled, it's boring. It's meaningless."

He swallows, dipping his tongue out of his mouth as he carefully pulls his hand away from hers and dips it into his pocket to pull out a black velvet box. His chest rises as he sucks in a deep breath before turning to look up at Kate once more.

"So, Katherine Houghton Beckett…" He carefully opens the box, revealing a rather large diamond ring inside. "Will you do me the honour of making me the happiest man alive, of being my partner in crime and in life – always… Will you marry me?"

Her teeth dig into her bottom lip, pulling it into her mouth as tears continue to cascade down the frame of her face. She adjusts Joseph on her hip, tightening her grip as she carefully lowers the two of them so she can kneel before Castle, her face breaking out wide.

"Yes."

She didn't need time to think about it or process it, because her answer to spending the rest of her life with him would always be a yes. She never wanted anyone apart from him. He'd been there for her throughout everything, he'd seen her at her best and at her worst, he was her best friend, her partner, and the love of her life.

"Yes?" Castle asks, his face breaking out into a wide grin as Kate's head nods up and down vigorously and he quickly leans in, his lips colliding with Kate's in a passionate kiss.

They break apart as the small boy between them gurgles and giggles, his hands moving back and forth to push each of his parents and both of them grin and laugh down at him before their heads are turning back to face one another and carefully Rick pulls out the ring from the box before slipping it onto Kate's shaking hand.

It glistens in the light, her eyes dazed as she takes it in before making eye contact with him once more. "It's perfect, you're perfect." She shakes her lead, leaning back in to press her lips against his, her hand cupping his cheek, the cool metal so foreign yet so right fitted on her ring finger, pressed against the side of his cheek.

She pulls back, wiping away the tears that had stained her cheeks as she glances down to Joseph and presses her lips against the top of her head.

"Joseph and I have been planning this for months. Thank god he can't talk yet, or he would've blown it." Kate can't help but laugh, her hand gently stroking Joseph's head as she looks from Castle down to her son.

"Is that right, have you been helping your daddy plan the perfect, yet cheesy way to propose?" She cocks her head, her fingers running through Joseph's hair.

"Hey, it wasn't that cheesy!"

"Castle, you put it on our son's onesie. It's cheesy." She smirks at him, shaking her head.

"What would you have done if he had woken up when you were out and I'd gone up and changed him right then and there? Your little surprise would've been ruined."

"Oh, I took the baby cam with me when I went out." He shrugs, and Kate gasps, eyes widening as she smacks him playfully on the shoulder.

"Richard Castle, I can't believe you'd take the baby cam with you! If he'd been crying, I wouldn't have known!"

"He has his mother's lungs, you would've heard him."

She hits him again, gasping once more as she shakes her head at him, but Castle only grins wider at her before moving to wrap his arms around her and Joseph, his lips pressing against Kate's temple.

"We're getting married." He murmurs against her skin; can see the way her facelights up more as she turns to face him.

"We're really going to get married."

She can't help but lean in to kiss him once more, and as they pull back, they hear knocking coming from downstairs.

"That must be our first party guests!" Castle carefully gets to his feet, helping Kate up as he kisses her cheek before Joseph's, running his hand over his son's head. "You get him ready, I'll go let the guests in. Get ready for the party of a life time, Joe!"

She watches him rush off and her chest rises before falling as she glances down at her son resting his head against her chest.

Had you told her a year ago that she'd be having Richard Castle's baby, or that she'd be accepting his marriage proposal on the day of their son's first birthday party – she would've laughed in their face. Because it seemed like the most absurd thing – having a child with him, being a family.

But now, now she couldn't imagine anything else apart from being with him and having a family with him.

She quickly changed Joseph into the onesie, making sure the text was faced into her chest when she brought him downstairs to their friends and family. Though, Lanie and Martha had both spotted the ring on her finger before seeing the text on Joseph's onesie.

Everyone had been thrilled for them. The boys had hugged her, told Castle if he ever hurt her that they'd make him pay. Lanie couldn't help but tear up, and had joked about being the maid of honor, though Kate had taken it seriously and made sure Lanie knew that there was nobody else she'd want by her side helping her with this.

Her father had pulled her aside and told her how happy he was for her, revealed that a few months prior Castle had come to him for his blessing and Kate's heart had filled with more joy in that moment.

Martha and Alexis were over the moon; had told Kate they couldn't wait for her to officially be a part of their family and had thanked her for making Castle so happy and for bringing Joseph into the world.

Overall, the day had been memorable – even more memorable when Joseph took his first steps. It may have been a birthday Joseph wouldn't remember, but it would be one Kate remembered for a life time.