"You're insane," Kate grinned, tongue between her teeth as she flicked a handful of soapy bubbles towards her husband's face, as they washed the last of the dinner dishes. "There is no way time travel is a real thing."

"Beckett," Castle gasped, taking a step back in mock horror. "I can't believe you just said that. You've seen the evidence first hand. Don't be a hater."

Kate threw her head back and barked out a laugh, startling the kids from their positions on the living room floor. Lily, reading quietly on her belly, head perched in her hands and feet swinging distractedly above her, merely shifted her eyes to their direction. She was used to her parents' behaviour by now, not much phased her, and she was halfway through the copy of Pride, Prejudice and Zombies, Jake had given her for her birthday. The boys never liked to miss out on a joke, and they quickly abandoned the game of Candyland they had been playing with Poppy, in favour of getting in on their parents' fun. Poppy scowled in their direction and grunted unhappily, dragging herself to her feet to chase after her favourite boys.

"What's funny, Mommy?" Jake grinned, sliding on socked feet to the stools at the breakfast bar. Reese slid after his brother, crashing into the side of his stool and shoving Jake to move over and make room. Jake giggled and crawled over to the perch beside, letting Reese clambor up to the newly vacant seat. His brother grinned maniacally, apparently that was wordless boy speak for 'thanks', or some strange twin thing, but Kate shook her head at their antics and dried her hands on a towel before leaning over the counter in front of her boys.

"I was going to say Daddy's being goofy, but I think all three of my boys are pretty nuts."

"Hey," Castle joked, sidling up beside her at the counter, hauling Poppy up to sit beside him, atop the breakfast bar. "Mommy's being mean to Daddy, Poptart. You better tell her to be nice, or Santa will fill her stocking up with coal."

Poppy giggled and set both hands on Castle's cheeks, loving the way he made silly faces to make her laugh. "Mommy be nice 'my Daddy. He my Daddy. Santa not come if you mean." She beamed at Castle, who shot Kate a smug look, before dropping a kiss to Poppy's dark curls.

"That's my girl."

"I'm so sorry, Baby," Kate joked dramatically, reaching over to tickle Poppy's chubby toddler belly, grinning at the squeals of delight. "Daddy is just so silly sometimes, isn't he?"

The boys watched with amusement, totally enamored with their little sister's happiness. It was unusual really, at least from what Kate had seen from her little interaction with children before her own. Her boys were seven-year-old rough and tumble, best of friends, grubby fingers and giggles when anyone said the word 'butt' or any derivative of the human posterior, but they adored everything about the little girl, and were gentle and completely happy to be entertaining her. They had their moments of annoyance at being pestered by a three-year-old, especially when they were engrossed in a video game, or closed up in Rick's office to watch cartoons Poppy wasn't quite ready for, but for the most part they loved to be with her. Kate reached out to squeeze their small hands, and winked at the twins. Lily sighed, in the living room, and carefully marked her place in the book before rising to her feet to join her family in the kitchen.

"You guys are all a little crazy, I think," she sighed again, but Kate saw through the façade of annoyance, to the playful heart of her firstborn. She ran a hand through Lily's long dark hair, and pulled her in to her side, tucking her in under her mother's arm.

"Sorry Tiger-Lily. Did we interrupt your reading?"

Lily shrugged and looked up at Kate. "It's okay. I just finished the chapter. What's everyone giggling about?"

"Daddy silly," Poppy blurted, provoking Rick into more belly tickles, while the rest looked on in amusement.

"Yep. We're all laughing at Daddy," Kate grinned, sticking her tongue out at her husband, who continued the routine of mock annoyance. "He still thinks time travel is a real thing, even after Mommy tells him over and over again, that it's impossible."

Poppy and the boys giggled at their mother's playfulness, and Lily just rolled her eyes, the perfect mini-Kate, if Castle had ever seen one. "It is totally possible, and Mommy and I have even met a man from the future."

"Simon Doyle was not from the future Castle," Kate groaned, for real this time, and she shifted slightly so she could look at him straight on. "He was just a man, who had some…" she quickly glanced at the kids, watching her expectantly, as she searched for diplomacy, "issues."

"He was totally from the future," Castle shook his head and grinned at the kids. "He knew things."

"I know things too, Castle. Like there's no such thing as time travel. Plus, he was totally wrong about everything he told you."

"Actually," Castle rebutted, and Kate groaned inwardly at falling victim to her husband's bait. "He wasn't necessarily wrong at all." He focussed his attention once again to the kids, lowering himself to the counter in front, so he could rest on forearms in front of the boys. Poppy patted him on the head with a chubby hand, apparently permission to continue, and Kate huffed in annoyance beside him. "Simon Doyle said he was from the year 2035 and that Mommy and Daddy were married and still lived here in New York."

"He also said I was a Senator, and I am most assuredly, not a Senator," Kate rebutted.

"Yet," Castle winked at the boys, still loving how he managed to get under Kate's skin with very little effort. "You're not a Senator, yet."

"There's still time, Mommy," Reese joined in. "2035 is still 9 years away. Lots can happen in 9 years, right Dad?"

"You bet Peanut," Castle grinned, reaching out to rustle his eldest son's hair. "Mommy could definitely be a senator by then."

"He also said you wrote serious literature," Kate continued her assault on his theory. "I still don't see anything serious coming from your imagination any time soon."

"I'll show you serious, Captain," Rick lowered the timbre of his voice, waggling his eyebrows suggestively. "Wait until bedtime and I'll show you just how serious my imagination can be."

"Are they talking about sex?" Jake poked at Reese's shoulder. Castle shot to his feet.

"Wait, what?"

"Castle," Kate hissed, through clenched teeth.

"Who's talking about sex? How do you know about sex?" Rick sputtered, shocked. "Nobody's talking about sex."

"Stop saying sex," Kate hissed again.

Poppy looked between them all, baffled at the drastic turn the conversation had taken, and Lily groaned and buried her face in her hands.

"I have an idea," Castle blurted, attempting to recover the situation. "For a book. It's not my usual genre, that's all I meant."

Kate's expression softened and she reached out to set hers atop his. "You never told me that."

Castle shrugged self deprecatingly, "I wanted to flesh it out first, see if there was anything there before I pitched it to anyone."

Beckett rose up on her bare toes and kissed his cheek softly. "It'll be great Babe, I have complete faith in you." Lily sighed again, and Kate took pity on the ten-year-old, the smirk once again finding it's way to her face. "But you're forgetting the most important piece of evidence against your time traveller theory."

Castle took her cue and resumed his mock defensive stance, winking once again at Poppy, to draw her back to the silliness. "Oh yeah, and what's that?"

"Simon Doyle said we lived in New York with our three children. Three, Castle. Why don't you go ahead and do a head count right now and tell me what number you come up with." She folded her arms across her chest in triumph, satisfied she had finally settled the debate.

"That's simple," Castle dismissed, with a wave of his hand. "It's semantics, really."

"I can't believe I'm saying this," Kate groaned, "but how is it semantics, really?"

"What's today's date Tiger-Lily?" Castle questioned the girl, her head cocking as she was drawn into the conversation.

"Um, it's December 15th," Lily offered. "Two thousand and twenty-six."

"That's right," Castle grinned at his daughter. "And how old are you kids, Jakey?"

"Lily just turned ten last week," Jake grinned at his sister. "Reese and I are six and a half."

"I free," Poppy blurted again. "I free, Daddy."

"That's right Poptart. You are three. Good job." Poppy beamed at the praise from her father, and watched him intently as he continued his argument.

"We've already established that the year was, or actually is yet to be, 2035, which Reese has so astutely determined to be nine years away. For the sake of accuracy, and since 2026 is almost over, we'll say eight years. Why don't you tell us how old you will be in eight years, Peanut."

"I don't know how old Lex is, but she'll be super old," Reese began, smiling happily at his parent's twin mutters of indignation at the backhanded insult. "Jakey and I will be," he paused to count on his fingers.

"Fifteen," Jake stage whispered beside him, bringing a scowl to Reese's face.

"I know!" Reese huffed. "Let me do it."

"You're doing great, Baby," Kate brushed a lock of hair from his forehead and shot Jake a disapproving look. The boy shrank back at his mother's expression.

"I free," Poppy shrieked, cutting the tension in the room, with her gift of perfect timing. She was her grandmother's girl, through and through.

Castle chuckled and pulled his daughter closer to his chest. "You, munchkin are three now, but in eight more years Poppy will be?" he looked back at Reese, their struggling mathmatician, for confirmation.

"Eleven," Reese exclaimed, proudly.

"Yay Reesey," Poppy clapped her hands for her brother.

"Eleven is correct. Now, most importantly, Peanut Butter, how old will Lily be?"

Lily frowned slightly, unsure of the direction the conversation was taking, and saw a similar expression cross her mother's face.

"Um, Lily will be," he paused, counting on his fingers. "Eighteen?" he looked to his mother, who smiled and nodded her agreement.

"Aha!" Rick shouted, drawing a delighted shriek from Poppy, and a startled Kate pulled a hand to her chest in reflex. Some small part of him hated that she still recoiled, still covered her very first bullet wound when she was surprised, but he recovered quickly, as did Kate, when the kids' giggles rang through the kitchen. "Eighteen! And where will you be when you are eighteen, Tiger-Lily?"

Kate finally caught on to the direction of the conversation and mentally berated herself for issuing a throw down when it came to Richard Castle and his myriad of fantastical theories.

"Prison?" Lily asked innocently, and pride exploded in Kate's chest like fireworks. Oh how much her daughter resembled her, in every way. No one else but her, and occasionally Alexis, could get that slack jawed expression on Castle's face, and yet, Lily had pulled it off effortlessly, while maintaining perfect composure. Martha would be so proud. She made a mental note to herself to call her mother in law later, to tell her all about her little divas.

"Prison?" Castle repeated. "You better not be. I meant college Lil, Jeez."

"Huh," Lily faked surprise. "Who says I'm going to college?"

Kate struggled to stifle the laugh as Castle's expression moved from confusion to sheer horror, all the way back to confusion in the space of five seconds. "Okay, you, I know you've somehow inherited your mother's witchy powers of distraction, so we're going to leave this conversation for another day. Don't think we're not done here though." He eyed his daughter warily, and she finally cracked, the dimple in her cheek appearing, as a smile blossomed on her face. Kate released a laugh and hauled Lily in for a tight hug.

"My baby. I'm so proud."

Castle muttered illegible sounds behind her, and Kate could hear Poppy giggling with the boys. "Anyway. Before I was so rudely interrupted by the Becketts over here," he gestured wildly towards Kate and Lily, and the two giggled softly, heads together conspiratorially. "I was about to prove a point. In the year 2035, where, or is it when, Simon Doyle is from, you and I live in New York with our three children, of which we have five. Alexis is already out, and in 2035, when Miss Lily is 18 years old, and in college, she won't be living with us, she'll be living in dorms, or the fanciest apartment her Daddy's money can buy, leaving us living here, in New York with Princess Poppy and the Dynamic Duo. Let's do that head count now shall we, Kate. One, two," he gently tapped Jake and Reese's dark heads of hair. "And three," more belly tickles for Poppy, who launched herself happily into Rick's arms. "Game, set, match."

Lily rolled her eyes and Kate just stared at him, unmoved by his passionate argument. "It should disturb me, how much you've worked this out, but sadly, I am no longer shocked by the levels of crazy you are capable of. There is no such thing as time travel, and you still can't prove it, no matter how much you argue." Castle grumbled again, mostly for show, and Kate stepped forward to plant a kiss on his cheek. "I'll tell you what. In 9 years, if the energy wars have come and gone, and I'm a Senator, and Lily's away at college when your serious literature comes out, I'm giving you the right to say 'I told you so.'"

"That's all I ask," he grinned and tugged her arms to wrap around his neck, kissing her hard. The kids groaned and scattered, small feet pounding on the staircase as they escaped to their rooms.

"I won this time. You're it for bathtime duty." Kate swatted his ass with a tea towel and darted, laughing towards their bedroom, dodging his grabbing hands.

"I'll get you later Kate Beckett," he shouted towards her retreating form. "Just you wait."

She turned back as she reached the doorway, bracing her hands on the jamb and leaning her head on the side, demurely. "I look forward to it."