Izuna pushed back half of Kitashi's sleeping yukata, kissing bare skin as it was revealed to him. She moaned softly in his ear and leaned forward to return the favor when suddenly, Himiko burst into tears. Kitashi jerked backward in surprise and Izuna regretted ever thinking that Himiko was a good, quiet baby.

Kitashi tugged her yukata back into place and made to stand up. Izuna gestured for her to stay in bed. "You took care of her last time, I'll see if I can get her to quiet back down. I think I'll leave her with Madara tonight."

"Are you sure?" she asked him.

"Madara doesn't have a mission tomorrow, it'll be fine. And Himiko should get used to sleeping with different people anyway. I'll be back in a few minutes," Izuna said over Himiko's squalling.

He went over to the corner of the room where they had nestled her into a little bed while they were occupied with other things. She continued to wail incessantly until he scooped her up, at which point she abruptly fell silent except for her sniffling. Izuna wasn't fooled. This wasn't the first time Himiko had done this and he knew that if he put her back down now, she'd only start back up again.

Izuna rocked her slightly as he exited the bedroom. "You're a better cockblocker than the most nosy grandma, Himiko-chan. Why don't you stay asleep and let us have our alone time? I think you'd like having a younger sibling to boss around, and I'd sure like to relax a little bit." Izuna's tone soured on the last part.

All week Himiko's crying had stopped Izuna and Kitashi from having sex. She seemed to have an uncanny ability to know when they were just starting. No matter if they changed the time of night or let Himiko stay in bed with them or moved her to a small bed of her own, Himiko would cry until they stopped. Quite frankly, Izuna was sick of it. She never cried any other time; it was as if she specifically didn't want them to have sex with each other.

Izuna silently made his way to Madara's room. He knocked quietly on the door frame and upon hearing his older brother murmur an answer, he entered the room. Inside, Madara hadn't quite made it to bed yet. It had probably been another long night of him approving team rosters for patrols and missions.

"What is it, Izuna?" Madara's eyes swept over him out of habit, and his brows rose slightly as he took in Himiko swaddled in Izuna's arms.

Izuna held out his daughter to Madara, who took her with some confusion. "She's sleeping with you tonight," Izuna said shortly.

"And why's that?" A hint of grouchiness entered his voice though Madara cradled her gently all the same.

"Because I haven't had sex all week and I'd very much like to have some alone time with Kitashi. It's okay if she doesn't sleep right away, she'll just sleep in late. Change her as soon as you wake up. I'll be back in the morning to get her." With that, Izuna turned on his heel to go back to bed.

"Hey wait, Izuna, you can't just dump your brat on me—"

"She's not just my brat, she's also the closest thing you have to an heir until you either have a kid yourself or you take her so that I can get started on the next one for you. So just watch her tonight and a few other nights while I work on having a son or two for you," Izuna replied.

Madara frowned at him sulkily. "But what am I even supposed to do with her?"

"Madara, she's not that complicated. All she does is eat, shit, and sleep. Keep her clean and fed until I come back. She doesn't cry unless I'm trying to get some, so she shouldn't be upset at all." Izuna narrowed his eyes at Madara. "Unless you do something to make her upset."

"She better not act up or I'm putting her outside," Madara grumbled. As Izuna left, he heard Madara start to mutter at Himiko quietly.

"Now don't you cry or do anything to get me in trouble with Izuna, because even though he's just a brat like you, I'm sure he'd manage to find a way to murder me if you cried even a little bit…"

Izuna smirked to himself. As if he was the only one who doted on Himiko. Pleased with his solution, he made his way back to his and Kitashi's bedroom only to find when he got there that Kitashi had dozed off waiting for him. He sighed. Another night then.

Himiko was furious.

It was the tense muscles, fist clenching, stand on your toes sort of anger that made her long for a wall to put her fist through. Unfortunately for her, Himiko wasn't even capable of standing on her own two feet unassisted, let alone property damage, unless one counted drooling on other people's clothes. Himiko was petty enough to do just that.

In another life time, Himiko had been enjoying life. She had graduated from college, was accepted into graduate school, was looking forward to the upcoming academic year and her new job… and it all ended before it even really got started. Next thing she knew, she was opening her eyes to a world where they didn't even have the courtesy to speak her language.

At least Himiko had gone to school for Japanese.

She might have been less pissed off if she had been reborn in the same world as her own previous one. It would have annoyed her to no end to have to redo her entire life, but she could work with that. Even do things differently, more efficiently. Maybe even be less of an asshole to people this time around. But instead, Himiko was in fucking Ninjaland, and as far as she knew, they didn't have college in Naruto.

Whoever stuck her here wasn't too nice about it either. Himiko couldn't have been born into an era of peace. No, she was born in an era of endless war, as evidenced by the fact that her father was Uchiha Izuna. She wasn't just reborn, she was reborn as a shitty plot device for a bad fanfiction of a shounen manga in the middle of a massive, ongoing war.

And that wasn't even the end of it. Himiko had been reborn, with everything that implied. She was stuck as a baby, and she magically had all the adult mental faculties to be completely unappreciative of it. She didn't know how she was able to retain all her previous knowledge and her former identity, since as far as she knew, she shouldn't even have object permanence. But somehow she was present for every single humiliating bit of childhood, from the lack of bladder control to the misery of teething.

If there was one thing she wasn't going to put up with though, it was two people having sex while she was in the same room, especially when those two people were supposed to be her new parents. Himiko normally avoided crying because she was pretty sure no one deserved the singularly unique punishment of a wailing baby, but she was starting to find interrupting the pair of teenagers pretty funny. It even got her what she wanted, which was to be very far away from Izuna and Kitashi while they had their alone time. No wonder babies cried so much.

In the morning, it wasn't Izuna who came to retrieve her from Madara, but Kitashi. Himiko didn't bother trying to parse Madara's low tones; there were only so many things he was probably telling her mother, and Himiko hated Japanese contractions and male patterned speech with the passion of a thousand suns. Well, more like a hundred. She'd save the thousand sun hatred for things like academic translations, esoteric kanji, and Classical Japanese.

Kitashi scooped Himiko up into her arms, her short, pin straight hair swinging just above Himiko's reach. "Madara says you were good for him, Hime-chan. Why can't you be quiet for your father and I, hmm?" Kitashi bounced her slightly.

Himiko thought about ignoring her, the way she had for several weeks after her birth, before she remembered Kitashi's worries about being a mother. With an inward sigh, Himiko cooed at her and opened her mouth in what she hoped was an approximation of a smile.

Kitashi beamed at her. "Well, at least you're a good baby the rest of the time. We'll just have you spend more time with your Uncle Madara, how's that?"

Anything to get away from sex happening right before her eyes. And, honestly, Himiko thought she could spend the rest of her life enjoying the strangeness of Uchiha Madara, one of the fiercest and most talented shinobi to have ever lived, doing something so mundane as paperwork. It was better than the alternative she was imagining, where she trained to become a shinobi and took missions and fought until someone killed her and left her body in a ditch somewhere.

Kitashi spoke with Madara a few moments more about something that Himiko allowed to pass over her head. She might have felt bad about not trying harder to decipher their conversation, except that even the passive listening to a language allowed for some form of acquisition. Thank god Himiko had studied child language acquisition before she kicked the bucket. Not that her interest in linguistics and foreign languages was going to serve her well in her new life.

Himiko gummed on Kitashi's folded collar, drooling all over the cloth with petty delight. The woman didn't outwardly react, so Himiko wasn't sure how she actually felt about the behavior, but it made Himiko feel better. Eventually, Kitashi left Madara to do whatever business she had that day, which turned out to be what Himiko felt was the shinobi equivalent of a stitch and bitch session.

Kitashi regularly met with a group of women that she had once told her were Himiko's aunts. There was Wakana, who was some kind of poisons and antidote specialist, and a new mother herself. Her son, Himiko had been surprised to find out, was Kagami, the future ancestor to Shisui. Or maybe he was Shisui's father. There had been conflicting canon information about that, Himiko recalled. Either way, Kitashi often plopped Himiko down with Kagami and expected them to play together or something. Not that Himiko did much playing at less than a year old.

The other women included Tomoe, who seemed to draw all the explosive and storage seals that the clan needed. Himiko thought that was quite a bit of work for a single person. Surely copying seals could be done by more than one person, especially in a clan that had a doujutsu that could literally copy writing. And then finally there was Mameha, one of the blacksmiths of the Uchiha. Himiko assumed she was not only talented at it but creative as well; Mameha had designed her own prosthetic leg out of some kind of complex mechanism that shifted with her weight and gave her a gait that, to Himiko's untrained eyes, looked the same as anyone else's.

If they weren't bringing along something related to their personal skills to work on, then they were bringing the armor and weaponry of their individual families for basic maintenance, or clothing to hem and sew. Today, Kitashi had brought along not only her kit but what Himiko already recognized as Izuna's as well. Himiko still hadn't divined what exactly Kitashi's role in the clan was beyond "murder people for money". Surely being Izuna's wife meant she had some greater responsibility. So far, if she wasn't away on a mission, she was home taking care of Himiko and making sure their household didn't fall apart around Izuna and Madara's ears.

When Kitashi arrived to the designated meeting place, everyone else was already present.

"You're late," Mameha said. Her deft fingers were already at work sharpening kunai. The scrolls next to her suggested she had quite a workload.

"I had to pick up Hime-chan from Madara. She's been getting fussy with us at night, so Izuna thought the change might get her to settle," Kitashi replied. Himiko would've snorted if she could. What a way of saying that he wanted to have sex with her without a crying baby in the room.

"How strange." Wakana had sewing out today. She was watching Kagami not at all, instead letting him crawl freely about the room. "Kagami-chan has finally stopped crying at every little thing. I wonder what it is that's making Himiko-chan cry."

Kitashi settled Himiko down on the floor next to her seat cushion at the table. Himiko looked over to Kagami, who was excitedly crawling after a ball. She was definitely not doing that. She had some standards still. Instead, Himiko looked across the table as best as she was able.

Kitashi sat next to Tomoe, which meant that Himiko had a perfect view of the explosive seals she was painstakingly drawing, over and over again. Himiko grabbed her ankles to hold herself upright as she watched. The character was vaguely familiar to Himiko, but highly stylized in a way she wasn't used to. She supposed she should consider herself lucky that it wasn't written in some medieval or classical version of Japanese.

Tomoe didn't even glance at her. "I don't have time to play with you, Himiko-chan, and if you get into my ink, I won't be pleased."

"Does she even understand that many words yet?" Mameha asked.

"She'll understand she's being told 'no'," Wakana said. "Himiko-chan, go play with Kagami-chan. You're not old enough to help us yet." As she spoke, Wakana stood, likely to pull Himiko away from the table.

"Nonsense Wakana-chan, Hime-chan knows how to behave. She won't be a bother." Kitashi smoothed down one of the stubborn spikes of hair that Himiko had already developed.

Mameha snorted. "She's Izuna's child, she won't be anything but a bother. A sly, sneaky little bother."

Himiko ignored them in favor of continuing to watch Tomoe work. It took her no time at all to draw each seal, and no matter how much Himiko strained her eyes, she could not divine the method Tomoe used to imbue them with explosive power. Did the user push their own chakra into the paper? Was there chakra in the ink? It was a mystery. When she was done, she released a controlled breath across the paper, causing heat waves to shimmer in the air. After the ink was dry from her breathing, Tomoe set aside in a neat stack to start the next. It was completely fascinating to Himiko.

"Look, she just wants to watch, see?" Kitashi leaned down by Himiko's ear. "If you're going to be up here, you have to stay out of the way, okay? Tomoe-chan is doing important work for the clan, so don't pester her."

Himiko babbled something back in response. It didn't matter how much she understood if she couldn't get her tongue and jaw to move just so to form coherent syllables, and for that she needed to practice speaking. For now, she was more or less limited to reduplicated syllables consisting of vowels and some labial consonants. At least her linguistic systems were developing normally.

Either way, it was good enough for Kitashi. She pulled out some weaponry from one of the two kits she brought with her and got to work maintaining them. As she settled in, the conversation started up once more. Some of it was gossip about various clan members, some of whom Himiko knew of and many more she didn't. Some of it was the kind of giggling that Himiko was familiar with from her previous life. And then some of it was distinctly shinobi in nature.

"More and more Igasaki have been pushing through River Country, fleeing from Wind," Tomoe murmured while she worked. "Hikaku told me."

"So it's true then, the Siege of Okayama was successful." Wakana frowned into her sewing.

Kitashi shrugged. "As long as they don't enter Uchiha territory in Fire Country, it's not a problem."

Wakana looked up at that, giving Kitashi a dry look. "You know they won't do that. They'll probably try that trick they did at Mikatagahara, the one where they walk in and try to destroy everything from the inside out. Not a bad tactic for a small clan."

"A tactic that won't work on us," Kitashi countered smoothly. "If they try to attack us, we'll eliminate them. If they're that desperate, they can join us as a vassal clan."

"Unlikely; we're already getting word from patrols that they're hostile. They're running scared, and it's making them stupid," Mameha said.

"Have order requests gone up? They have for explosive notes," Tomoe said to Mameha.

"Tch, of course they have. We're going to need another run for more steel. And we need to train our squads to stop being so damn wasteful, or at least pick over the corpses better; we can't keep up with demand," Mameha replied.

Tomoe gave Mameha a reproving look, but Himiko was distracted from her response when something nudged her in the back. It took a bit of wiggling and undignified rolling, but Himiko turned around to see Kagami and the red ball. She heaved a sigh internally. With clumsy hands, she grasped the ball and threw it less than gracefully. Kagami didn't seem to mind, and went off chasing after it again.

It wasn't long before he returned, ready to engage her again. Himiko rolled the ball to him this time. It wasn't as if she completely followed the conversation anyway; too many words she didn't know and her brain was tired from the constant processing. As long as Kagami didn't expect her to go crawling after the ball like an actual baby, Himiko could think of it like playing a very modified version of catch.

Soon enough, the two of them were listing to the side. Neither of them could keep themselves from yawning. Not for the first time, Himiko cursed her infancy. She was contemplating going to sleep against Kitashi when the door slid open.

Himiko rolled around to spy Izuna standing in the doorway, a young boy peering around his legs. Himiko recognized him as Setsuna, an orphan that Izuna was mentoring. His face was flush with emotion and exertion. Izuna nudged him inside and slid the door shut behind them when they had cleared the way.

"Go away, we're busy," Mameha said flatly.

"Charming as always, Mameha," Izuna replied. "Don't worry, I'm not here for you. We'll be quick, Setsuna just has something to ask Kitashi."

"What is it, Setsuna-kun?" Kitashi prompted, a smile starting to play around her mouth. Setsuna shuffled forward, but then seemed to draw on some source of confidence and tilted his chin up and pulled his shoulders back. It would've been more impressive if it hadn't been so obvious and exaggerated. Instead, he just looked funny.

"Kitashi-sama," he started. "Under Izuna-sama's mentorship, I was able to master Goukakyuu to the satisfaction of our clan head, Madara-sama." Setsuna swallowed. Himiko blinked open her eyes a little wider, impressed. Wasn't Goukakyuu supposed to be a C rank ninjutsu?

Setsuna continued on. "But I am still not yet a full shinobi of the Uchiha clan. If it pleases Kitashi-sama, would you do me the great favor of leading my first mission and allowing me to demonstrate my ability, so that I may join our ranks and defend the clan?" His words were slightly stilted and formal. It was probably a ceremonial phrase rather than something he came up with himself.

"Is that so?" Kitashi hummed. "You think you're ready to become a full shinobi of the Uchiha?"

Setsuna blinked, clearly not expecting Kitashi to hedge her answer. "Yes? I mean, yes, I do, Kitashi-sama."

"And why should Kitashi waste her time on a brat like you?" Mameha scowled at Setsuna. He puffed himself up in preparation for some retort when Tomoe interjected.

"Surely Izuna-sama wouldn't have brought him here if he didn't think Setsuna-kun was ready."

As Setsuna's eyes drifted from Mameha to Tomoe, Mameha's scowl dropped into a grin. So she was hazing him, Himiko thought. Even asking for a mission leader was a test.

"That's right, Tomoe-oneesan. If Izuna-sama thinks I'm ready, then I must be," Setsuna said, recovered from the unexpected exchange.

Mameha scoffed. "Izuna-sama, Izuna-sama, is that all you care about? Show some independent thinking, boy."

Izuna leaned against the wall as Setsuna visibly struggled to come up with an answer to Mameha. He seemed content to let the boy flounder on his own. Himiko couldn't tell if that was because Izuna was confident that Kitashi would say yes or because he just wasn't supposed to interfere at all.

She squinted her eyes at Izuna while the others continued to talk around her. At this age, with his face structure still changing in subtle ways, he could still pass as Madara's twin, were it not for his fuller lips and Madara's heavy eyes. She didn't think either of them had the Mangekyou yet, but then, there was no reason for either of them to show off that particular trump card in front of her. Himiko still couldn't believe she had gotten stuck in the Uchiha clan of all clans, in all eras, of Naruto. Bullshit.

Izuna seemed to notice her regard at last. "What is it, Himiko-chan? You look grumpy again."

"She's been playing with Kagami-chan," Kitashi said, breaking out of the exchange with Setsuna and her peers. "She's probably tired."

"Is she still drooling everywhere?" he asked. Without waiting for a reply, he bent down and scooped up Himiko. She answered for Kitashi by immediately biting down on his collar. Above her head, Izuna sighed.

Kitashi returned to the conversation at hand. "That's enough, Mameha, I've come to my decision."

Setsuna fixed his eyes on Kitashi. The serious mien he had been trying to adopt fell away and his expression became hopeful. A little boy who couldn't wait to become a man via murder, Himiko thought with disgust.

"I will lead your first mission, but I'll be deciding what mission you take. And a successful mission won't necessarily mean I'll allow you to become a fully fledged shinobi." Kitashi narrowed her eyes. "You'll have to impress me."

Setsuna bowed, almost falling over in his excitement. "I understand, Kitashi-sama! I won't disappoint you!"

Izuna deposited Himiko back on the floor next to Kitashi. "You'd best not, or you'll have me to deal with. Let's go Setsuna, before Mameha tries to set us on fire for interrupting their work."

Mameha snorted but had already gone back to her weapons sharpening and polishing. Himiko rolled closer to Kitashi when it became clear that none of the adults were interested in interacting with her again. Good. She wanted more sleep. She dozed off watching Tomoe create more seals, the rasp of weaponry and feminine giggling in her ears.

Apparently, the mission Kitashi wanted for Setsuna hadn't come yet. It had been two weeks since that encounter and Kitashi remained at home. Himiko spent her nights with Madara now, tucked up against his side with his hair well within her reach. It gave her no small amount of joy to tangle her fingers in it and listen to him curse in the morning as he tried to free himself from her grip.

Setsuna drifted in and out, dropping by daily in the hopes that Kitashi would inform him that tomorrow would be the day that they would go on his first mission. Neither Izuna nor Kitashi dissuaded him, and both seemed to be amused by him instead. Other clan members also came and went, disappearing for days or weeks at a time on missions, checking in with Izuna or Madara, with some occasionally deigning to speak to her. Most did not, and so the majority of Himiko's input came from Kitashi, Izuna, and Madara.

During one such day, it occurred to Himiko that it was probably useful. After all, even though she had no intentions of becoming a shinobi, the related vocabulary was no doubt going to be useful for her. And so she dutifully listened to Kitashi's sing song voice that recited macabre words during their games.

"There are eight points, Hime-chan," Kitashi began. "And they go like this: Larynx!" Here Kitashi tickled at Himiko's throat until she giggled reflexively, trying ineffectually to bat away her mother's fingers.

"Spine! Lungs! Liver!" Kitashi's hands darted to Himiko's back, to her chest, and then to her stomach. Himiko chased them all the while, trying to protect her sensitive skin.

Too late, Kitashi was on the move again. "Jugular! Subclavian artery! Kidneys! Heart!" The tickling continued, with Kitashi starting a new list of vulnerable parts of the body and pointing them out on Himiko in turn. Himiko's laughter rose into a shriek as her mother continued.

"Mama!" she shouted, in lieu of being able to tell her to stop. Kitashi froze all the same.

"What was that, Hime-chan?"

Himiko kicked her legs, glad for the tickling to be over. "Mama," she repeated.

Kitashi's dark eyes became glassy, and then, to Himiko's shock, the black faded into bright crimson, and suddenly her mother's Sharingan was staring down at her.

"Oh, I love you so much." Kitashi scooped her up to hold her close to her chest. Her pulse thumped slow but clear, the sound comforting to Himiko.

"Mama," Himiko said again.

"I have to show Izuna. He'll be so proud of you. Let's go show your father what you can do, okay?" Kitashi stood from where she had been kneeling on the floor.

Himiko was proud of herself. This was the first comprehensible thing she had ever managed to say in this tiny body, and for a baby, it was fairly complex. She couldn't wait for her mouth to finish catching up to her mental lexicon. After that, she groused to herself, she would have to work on controlling her bladder.

Kitashi raced through the halls to Madara's office. Inside, Izuna and Madara were bowed low over some paperwork of some kind or another. She didn't even bother to announce herself. She just swept inside and settled down next to Izuna.

"Izuna, you have to listen to this," she said breathlessly. Kitashi set Himiko down on the table, uncaring if the papers were wrinkled beneath her form.

"Hime-chan, who am I?" Kitashi leaned forward eagerly.

Himiko smiled, finding Kitashi's excitement infectious. "Mama!"

Kitashi dropped kisses all over Himiko's face. She sneezed when her mother's face tickled her nose. "You're such a good girl. I'm so proud of you." She turned to Izuna.

"She can talk now! We were playing and she called me mama." Kitashi took Himiko in hand again, angling her towards Izuna.

"Do you know who this is?" Kitashi asked.

Himiko took note of the Sharingan in Izuna and Madara's eyes. Was this because of the emotion of the moment, or because they wanted to memorize this moment with their doujutsu? Either way, it was intimidating to be stared at by red eyes. It just wasn't natural. At least there was no Mangekyou peering at her, but a standard, fully mature Sharingan.

After a sufficient pause, where Himiko fumbled with her tongue in her mouth, she said, "Dada."

"No way," Izuna breathed. Himiko reached for him. What an idiot, she thought, feeling a little fond. There was no way he had mistaken what she had said.

"Dada," she said. With a little effort, she waved her fist at Madara. "Grandpa."

"Excuse me," Madara's voice came out affronted. "I am not your grandfather."

Himiko grimaced. She hoped she would figure out this vowel thing sooner rather than later. And pitch-accent. And contractions. And...there were so many things she needed to work on. She tried again.

"Uncle. Mama. Dada." Pleased with herself, Himiko repeated herself a few more times for practice before lapsing into silence. That was good enough for now, and she was getting both hungry and tired.

Kitashi kissed her head and then brushed back her hair with her fingers. "Our baby can talk now, Izuna."

He nodded, his face slightly slack. People could get awfully dumb about their kids, Himiko thought. Babies spoke sooner or later, provided they had enough input and interaction. It wasn't something to be struck dumb by. Himiko let herself fall backward. Maybe she would eat when she woke up instead. Talking was hard work.

It was only a few days later that Kitashi left. Himiko had watched with no small amount of fascination as the woman she knew as her mother turned into a capable young shinobi, her body armored and outfitted with any number of weapons. But the real shock had been, as Kitashi left Himiko in Wakana's care, they had shared a passionate kiss. Himiko was mostly aware that Kitashi and Izuna had married for convenience, but she never would have guessed that her mother had a romance with Wakana. It explained why they spent so much time together.

Wakana took over for Kitashi seamlessly. When Izuna was busy, Wakana tended to Himiko, toting her everywhere alongside Kagami. She doted on Himiko the same way she did her own son, and so it was no small chore for Himiko to coo and call her Aunt. Her babbles delighted Wakana into showing Koyane Himiko's new found verbalness.

It was only after Kitashi went on her mission with Setsuna that Himiko finally returned to sleeping with Izuna. With no wife, and presumably therefore no sex, Himiko had no reason to cry at night to spare her senses. She gave Izuna the same treatment she did Madara, helplessly tangling her hand in his long ponytail. Unlike his older brother, Izuna seemed charmed by it.

On the fourth morning of Kitashi's absence, a knock came at the door. Izuna finished shrugging into his day clothes before answering it, revealing Shinatsu, another member of the main house.

"It's a bit early, isn't it, Shinatsu? Where's Kitashi and the rest of the squad?"

Shinatsu's face drew into an expression that pulled oddly on the tattoos on his cheeks, giving him a foreboding atmosphere. "That's why I'm here, Izuna. There's no easy way to say this, you know that, but…"

"Spit it out," Izuna snapped, his back already tense with anticipation and realization.

"It's Kitashi. She didn't make it."

The eight points Kitashi recites are from Zabuza's opening monologue to Team 7 in the Wave arc.

A note on Himiko's developing speech: in my mind, what she's actually saying is "kaa-chan" (Mama), which, for a baby, is very complicated. Babies typically say vowels first, then a set of consonants called "labial consonants", basically, "m", "p", and "b". "G" and "k" come later, and the "ch" sound even later than that. To string this all together as a comprehensible word, and not just repeated sounds "mamabobogaga" etc is very remarkable for a child less than twelve months.

That said, in Japanese, the words for "grandpa" and "uncle" are very similar; "grandpa" is "jii-chan" with a long vowel, and un"uncle" is "ji-chan" with a short vowel. It's a very common mistake for English speakers when studying Japanese to mix those up, because in English, long and short vowels are not used to distinguish two different words (what is known as minimal pairs. Compare "pat" and "bat", where "p" and "b" are used to distinguish the two words). This is why Himiko accidentally calls Madara "grandpa" at first.