AN: I'm sorry if the update isn't the next chapter of the Seirin meeting Vongola yet. But, this is what I wanted to share first (and it won't be the last but it'll be a while by then) so, Enjoy. And, if you're interested in another KnB-KHR crossover, check out my other story of "Phantom Tutor". I'll try to update as soon as I can, though.

Warning(s): A little OOC. Some OCs (Kuroko's mother and other Vongola children).

Pairing(s): None as of yet.

Disclaimer: I don't own Kuroko no Basuke or Katekyo Hitman Reborn.

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[Interlude: Childhood Years]

"Ne, ojii-san," A six year old teal haired boy called as he stood on the stool beside his grandfather. "When is tou-san coming back home?" He asked quietly as he watched the man skillfully slice and clean the tuna.

Yamamoto Tsuyoshi hummed under his breath as he contemplated the question.

"I don't know," The man answered with a frown. "Your idiot father hadn't called yet," He grunted as he carefully put the tuna meat on a clean wooden plate. Though, he smiled when he saw the wide inquisitive blue eyes of his grandson.

"Are you making tou-san's favorite?" The boy asked curiously, cheeks puffed up a little.

"Maybe," Tsuyoshi grinned as he put the knives out of the child's reach. "That's why he better be home soon before I change my mind, don't you agree?"

The teal haired boy blinked and tilted his head.

"Hai!" He beamed as his eyes strayed back to the cleanly sliced tuna meat.

Tsuyoshi went to the sink to wash his hands while still keeping an eye on his grandson from the corner of his eye. The boy looked to be a male miniature version of Kuroko Senna. At first glance, Tetsuya didn't seem to have inherited anything from Takeshi but Tsuyoshi had raised his own son to be able to recognize Takeshi's face in the teal haired boy. They also seemed to possess observant personalities and Tetsuya also had Takeshi's keen eyes as well.

While he disapproved of how Takeshi became an early father at the age of twenty, Tsuyoshi would never reject Tetsuya for it.

Sighing, he wiped his hands clean before approaching his grandson and lifting him off the stool. Placing him on the ground, he marveled at how small his grandson was. He was informed of the premature labor that Senna had undergone but he still disliked the fact that it gave Tetsuya a frail constitution.

The boy had also inherited his mother's low presence, making her job effective as an assassin, and it didn't help that the boy was just too quiet sometimes. It was the reason why Tsuyoshi had to always keep an eye on Tetsuya unless he wanted to miss the boy if he overlooked him. He couldn't believe that, of all the things he could've inherited from his father, Tetsuya seemed to also have that same shyness from when Takeshi had been the same age.

"Ne, ojii-san," Tetsuya called him again as he looked at Tsuyoshi with those wide powder blue eyes. "Do you think tou-san's coming back today?" He questioned as he rubbed the back of his head, somewhat messing his teal locks.

Tsuyoshi couldn't help but frown. Takeshi said that he'd be gone for three days due to mafia business. And it was already two days past the deadline. He refused to worry but with Tetsuya repeatedly asking for his father, he couldn't help but start to grow concerned at the lack of contact that went with the absence.

"Don't worry about Takeshi," Tsuyoshi smiled as he ruffled the boy's teal hair. "Your father's a very strong man and, once he's back, make sure he knows that he made you very upset for being late, alright?" He stated good-naturedly with a grin.

Tetsuya looked at him hesitantly before giving a small soft smile, slightly assured.

"Hai," The boy agreed, ducking his head shyly.

"Well," Tsuyoshi grinned slyly. "Why don't we go out for some ice cream–" He was starting to ask in order to cheer the boy up but was cut off by the door of the shop slamming open.

Brown and blue eyes strayed to the source of the noise only to see the subject of their conversation standing there. Takeshi was dressed in his signature blue button-up shirt and slacks (the attire he had taken to wear ever since his eighteenth birthday and debut in the Vongola) but Tsuyoshi frowned at the bandages peeking out of the chest area and the ones around his son's head. The younger man also looked slightly disheveled and slightly worn out but the beam on his face was unmistaken.

"Tou-san?" Tetsuya called on hesitantly, as if he was uncertain if it was his father standing by the doorway.

If possible, Takeshi brightened further.

"Tetsuya!" The man enthusiastically exclaimed as he stepped into the shop and Tsuyoshi almost missed his grandson who had run towards Takeshi. To his credit, his son met Tetsuya halfway as he crouched on the ground and took the boy in his arms.

Standing up with the teal haired boy in his arms, Takeshi gave Tsuyoshi a tired but lopsided grin.

"Yo!" Takeshi greeted.

Tsuyoshi scowled, unimpressed.

"You're hurt," Tetsuya's soft voice was accusing as the boy's pale fingers gingerly touched the bandages around Takeshi's head, a troubled frown on his lips.

"When will you learn to be more careful?" Tsuyoshi asked lowly, his eyes meeting his son's for an intense second.

But, Takeshi avoided his gaze and merely focused it on the teal haired boy in his arms.

"Don't worry about it," The boy's father waved off with a laugh. "It's just a scratch. I'm sorry I'm late but I brought peace offerings?" Takeshi offered sheepishly as he brought up his hand to show the 'peace offering' that he had been bringing along for a while now, something that Tsuyoshi failed to notice before.

He suppressed a sigh. Tetsuya's eyes sparkled.

Takeshi laughed at his son's reaction upon sighting his gift.

"Vanilla milkshake!~" He sang as he waved the cold beverage in front of the boy. "Of course, I won't forget about my favorite little guy," Takeshi cooed as he nuzzled the boy's face with his own, making Tetsuya giggle slightly.

This time, Tsuyoshi did sigh, the boy was too soft on his father.

An eight year old Tetsuya awkwardly shifted on the bed as he watched his godfather pack his things.

"Is this all of it?" Gokudera Hayato grumpily asked as he settled the bag on the couch.

Tetsuya avoided the man's narrow-eyed gaze as he fumbled with his hands, somewhat nervous as he carefully slid off the bed. Thankfully, the ache in his joints was no longer present and there wasn't any heavy pressure on his limbs this time. In a way, it was understandable, considering that he had been bedridden for almost two weeks due to a high fever. He knew that his body's weak and it caused whatever illness he caught to be more severe compared to an average person.

That was why the family made sure that he rarely got sick and, as much as possible, not at all.

"Hai," He answered quietly as he moved to stand beside the silver haired man, one of his father's best friends.

"Are you sure, Tetsuya-san?" A slightly high-pitched voice asked and Tetsuya smiled at the silver haired boy standing by the doorway, Hayato's five year old son, Tohru. Brown eyes narrowed at him suspiciously as the boy ran into the room and inspected the teal haired boy by circling him.

"Tohru," Hayato ground out as he closed his eyes. "What are you doing here?"

The silver haired boy merely put his hands on his hips, staring at his father defiantly. It eerily reminded Tetsuya of Haru. He could see how his godfather's eye was twitching at the sight.

"Well, Kyoko-san brought me here!" The boy insisted as he stuck out his tongue at the man. "She's waiting outside with Tomomi-san. So, you can't tell me I'm sneaking around again!" Tohru declared with a huff, taking Tetsuya's hand in his own as he tugged the teal haired boy with him.

Hayato looked extremely ticked off at his own son's cheekiness, his jade eyes narrowing with annoyance.

"B-But, Tohru-kun–" Tetsuya reluctantly tugged Tohru back, his powder blue eyes shifting to stare at the man over his shoulder.

"Don't worry about that old man," Tohru waved off the older boy's concern. "He's just grumpy that kaa-chan threw away his cigarettes. Now, come on! Kyoko-san bought you vanilla cake!" He impatiently pulled the teal haired boy out of the room.

Tetsuya looked over his shoulder again to see his godfather's fuming form and decided that it was best to leave him be for the mean time.

Following his 'cousin', Tohru seemed to know his way around the hospital already. The silver haired boy had inherited his parents' keen intelligence and Tetsuya wondered how Hayato was faring with his son who was too smart for his own good. Even he sometimes felt exasperated because he was always pulled along whenever the other was sneaking around and meddling with things that their parents didn't want them to be part of.

Once they reached the lobby, they were both greeted by an auburn haired woman with a small brunette boy being supported by one of her arms, peering down at them with wide gold eyes that were similar to the woman's. Tetsuya bowed politely while Tohru merely continued to tug him.

"It's been a while, Kyoko-san," Tetsuya greeted with a smile.

The woman brightened upon seeing him, crouching down to give him a one-armed hug and a kiss to the forehead.

"I see that you're already better, Tetsu-kun," She said gently as she held his chin, inspecting his face closely. "We were worried about you. I'm sure Yamamoto-kun will be delighted to see you but he's taking care of some business with Tsu-kun, so I'm the one picking you up. Is that alright with you?" She tilted her head at him, soft smile in place, as her long auburn hair swept past her shoulder at the action.

"Hai," He simply nodded as he met Tomomi's wide eager eyes.

"Tetsu-nii! Tetsu-nii!" The toddler clapped enthusiastically. "You better now?" He asked with a wide grin, a tooth gap on the front row of his teeth.

Tetsuya smiled at the brown haired boy.

"I'm fine now, Tomomi-kun," He ruffled the short messy brown locks. "Thank you for asking," He nodded.

The toddler brightened at the gratitude.

"Yeah, yeah, yeah," Tohru cut in, waving off the toddler as he tugged Tetsuya's hand again. "Let's go, Kyoko-san! You said you'll bring us to your house!" He asserted impatiently, bouncing on his feet almost restlessly.

Kyoko stood up as she merely smiled at Tohru's eagerness.

Though, the silver boy yelped when Tetsuya pinched his side.

"Don't be impolite to Kyoko-san, Tohru-kun," He lightly reprimanded as the other boy appeared admonished and gave a sheepish smile to the auburn haired woman who giggled at their antics, Tomomi mimicking her.

"It's fine, Tetsu-kun," She shrugged it off as she held the teal haired boy's hand. "But we'll first have to wait for Gokudera-kun. After all, Tsu-kun will worry if we go around without a chaperone," Kyoko pointed out as she directed them to the seats by the walls near the lobby.

Tohru remained standing as he puffed out his cheeks.

"That's what I don't understand," He complained with a scowl, looking very much like his father now. "I don't get why we always need a bodyguard," He grumbled under his breath as he crossed his arms over his chest.

Tetsuya noted that Kyoko seemed to stiffen with nervousness.

Before he could question on it, though, Hayato chose that moment to step out into the lobby, carrying Tetsuya's bag over his shoulder.

"Oi, old man!" Tohru called out with annoyance. "Why are you so slow? We need to get going! Tetsuya-san needs his cake!" He pointed out as if his reason was actually valid, his brown eyes glaring accusingly at his father.

"Why you disrespectful little brat…" Hayato growled as he pulled Tohru up by the back of his shirt, the silver haired boy flailing wildly.

Kyoko chuckled as she stood up.

"Aren't they cute, Tetsu-kun?" She whispered down to him conspiratorially, a mischievous smile on her lips.

Tetsuya shrugged with a small smile of his own.

No matter what they did, this was his family. And he loved them.

Takeshi smiled as he watched the mesmerized glow of his son's face.

The ten year old teal haired boy didn't seem to hear him, his eyes still glued to the television screen where players were passing the ball, running around the court, and trying to score by shooting. While he couldn't convince his son to take up baseball, this was actually the first time that Tetsuya had taken an interest in a sport.

"Do you want to play basketball?" He couldn't help but ask.

The boy jumped, as if forgetting his presence (which was usually the other way around with other people), and hesitantly nodded his head.

Takeshi stood up with an excited grin.

"Well, why didn't you say so?" He laughed at the astonished expression on his son's normally composed expression. "But, it'll take some time to set up the court by our backyard. Though, you'll have to do with the street courts for a while," Takeshi advised as he watched a smile bloom on his son's face.

"Arigatou, tou-san," The boy said before stepping forward to hug him around the waist.

He ruffled the teal locks affectionately. The boy was too formal. This was his dad's fault, actually, since he had Tetsuya take up kendo a little early than he did. But, it was fine. Shamal had recommended that the boy should be engaged in physical activities to strengthen his immune system. And, since the boy didn't have active interest in any sport, it had been a hard time to deal with until Tsuyoshi had finally pushed Tetsuya into practicing kendo early.

"Why don't we go out for some vanilla milkshake first?" Takeshi contemplated as he looked out the window, it was still mid-afternoon.

"Hai!" Tetsuya agreed with more enthusiasm than he normally would.

Well, if basketball would make his son happy, who was Takeshi to refuse him?

"What are we doing here, Tsunayoshi-san?" A nine year old Tetsuya asked almost exasperatedly.

"Ssh!" The brunette man was quick to shush him, pulling the teal haired boy's baseball cap lower while pulling his own bucket hat down as well. "Normally, I would correct you about my name but I'm not going to be tempted into saying it out in the open," The brunette man told him seriously, his chocolate brown eyes roaming around the café they were settled in suspiciously before slumping in his seat.

"You haven't answered my question," The teal haired boy deadpanned.

At this, Tsuna smiled back at him shakily.

"You see, I've been cramped up in my office for three days now," The brunette started off, sounding innocent. "And the paperwork didn't seem to be decreasing no matter what I did. So, I'm currently taking a break, so to speak," He nodded sagely at this.

Well, his godfather had basically admitted that he just ditched his job to escape paperwork.

"I can understand that," Tetsuya nodded and watched as the man seemed to melt with relief, as if glad that someone understood his plight. "But what I don't understand is why am I here as well," He pointed out wryly, taking a sip of his milkshake.

"It's because Tetsuya-kun saw me," Tsuna pointed out as he crossed his arms over his chest. "And I can't leave any witnesses there, or else, all that sneaking out would've been for nothing," He was almost wailing by the end but seemed to have the sense to lower his volume.

"Uhm…" Tetsuya hesitated. "You know that tou-san always puts a tracking device on my person, right?"

"What?!" The brunette man shrieked as he instantly hovered over Tetsuya anxiously.

The teal haired boy decided to take pity on him by plucking out the button from his shirt which had a small blue glow. He became worried when Tsuna ripped it out of his grasp with an almost crazed look before smashing it in his fist. Not a moment after that, they were fleeing from the café and Tetsuya didn't know if he should regret his action. If this wasn't his godfather, he would've thought that he was just kidnapped.

Fortunately for Tsuna, five minutes just after they took off, the man's subordinates was swarming the café led by Hibari Kyouya.

"That herbivore…" The Cloud Guardian growled ominously.

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TBC.