"I don't understand what you're talking about. The Fourth didn't have any children and his last name definitely not Uzumaki. What gave you the idea that you were the Fourth children." Hiruzen said without a change in expression. His mind running a mile a minute trying to figure out how to deny any reasoning they had.
"Lair." Naruto spat out his first word since entering the office surprising the old man.
"You might not know this but as the nine tails jinchuriki we have the ability to sense negative emotions such as fear, anger, greed, guilt..." Naruto said the last one while looking into Hiruzen's eyes as if trying to peer into soul.
Hearing that The Third eyes just widen for a split second before returning to normal. This usually would be gone unnoticed by normal people and lower-level ninjas. But for Naruto and Izuna who had to live by basically reading the expressions of the people around them since they were three.
The old man just narrowed his eyes with an intense gaze. "Who told you that you where the nine tails jinchuriki?" He said with pressure radiating with every word. Angry at whoever disobey this order. First it was someone from his close council told the civilian side about the twin, then it spread among the common people.
'It seems that I have been too lenient.' Hiruzen thought to himself.
"Tailed beasts are basically large mass of chakra with a soul, so to say that someone killed it is impossible as of now. So, the only way to neutralize it would be sealing." Izuna explained while getting a surprised look from the Hokage.
"Also, we were born on the supposed day that the nine tails died. And it doesn't really help that the villagers been calling us demons every other minute. If anything, we could ask Kur- I meant the nine tails for confirmation."
Their last sentence almost gave the old Kage a stroke.
"D-Did you just say ask the nine tails? Meaning you can already communicate it?" The Third asked with a shakily voice. Clearly disturbed by this revelation.
To his question the twins just looked at each other for a brief moment before nodding their head in response.
Hiruzen took a deep breath before releasing it. He was about to say something but was interrupted but Izuna."Don't worry old man we won't release the seal until we completely trust him or have the confidence to beat him. I mean, our parents literally died to seal him so we can't just go around and release him."
The old Kage felt the need to inform the twins that they couldn't release the seal no matter what, that they couldn't trust the beast no matter what, but he knew that he couldn't deter these two children from the idea. His wondered to the suggestion that his friend and former teammate gave him a few minutes ago. He then shook his head to get rid of the thought. He couldn't do that the children of the hero who sacrificed not only himself, but also his family so that he could protect the village.
That then brought him to the reason why this conversation began. The identity of their father. But he was curious as to why they were so sure that the Fourth was their father. "But why the fourth specifically? It could be any shinobi who lost their life during the nine tails attack."
"We were born with pretty good memories being able remember most things from birth. Even without that, we look like the Fourth Hokage without the whiskers. His face is literally one of the most notable things in the village. But could be chalked down to being a coincidence since it's just a giant sculpture. What solidify it was that his picture is still in the office, and he looks similar to Naruto, minus the whiskers marks." Izuna stated in a matter-of-fact voice.
Hiruzen was surprised but he then sighed. He overlooked that such a simple thing. Similarities between parents and children. With that in mind he just gave up on convincing them otherwise.
"So, long had you did you know this for?" Hiruzen asked with a defeated tone.
"Probably about two to three months give or take." Naruto though for a moment before giving his response.
"So why now of all times did you choose to reveal your knowledge of this?"
"We got kicked out of the orphanage, so need a place to stay. Plus, Izuna thinks that it is time we start training in shinobi arts because all the clan kids started theirs."
The old man then raised his brow and looked at the black-haired child looking for an explanation.
"There is a reason why shinobis from clans usually outperform shinobis from civilian households. One, clans have specialized techniques and ways to train such techniques. And two, they start their training earlier than when they start the academy. Unless they are a genius, they usually have no hope to reach such height. For example, the Uchiha clan, teach their children the Fireball jutsu around this age. So, in order to not be left behind we such start now." Izuna explained the reasoning behind his decision.
Hiruzen when pondered for a while before he took out an empty scroll and started to write on it. In about twenty minutes he was finished. He then took out seven additional scrolls with two chakra paper and gave them to the twins.
"That scroll is for chakra control training. Those three is for the three basic shinobi arts they teach you in the academy. The rest of the scrolls are there to help you with the basic of ninjutsu, genjutsu, nature transformation and fuinjutsu, if you're interested. If you want to study more on fuinjutsu you can just go to library to learn more basic seals."
The fuinjutsu section of the library is basically opened to general population. This is because fuinjutsu is a dying art since the Uzumaki clan was destroyed. This was the Hokage way of trying to get more people to get into it. Fuinjutsu is an art that has a lot of diversity although it needs a certain level of preparation to be able use in battle. So, the old man hoped that the last two Uzumaki could have some interest in it.
"For taijutsu, you guys are a bit too young to be learn it for now. Don't worry about a place to stay or eat. You'll be living with me until the house is ready and after that someone will come weekly with grocery." Hiruzen said with a warm smile.
***
Then for the next month Naruto and Izuna were living with Hiruzen.
On the first day Izuna took out the scroll for chakra control training. He knew that if he could not control his chakra, he could forget about doing any jutsu.
He read through the training manual twice putting away the scroll. He realized that controlling wasn't any different than controlling spiritual energy but opted to use this world method before changing.
He then closed his eyes in a mediative pose trying to feel his chakra according to the method written on the scroll. It didn't take long as he opened them only a moment later. With a leaf in front of him he will his chakra to his index finger that was touching the leaf before willing it attach itself to the leaf. He then picked up finger, with the leaf following his finger before falling. With that he was ready to try the first chakra control method, the leaf concentration exercise.
He then placed a leaf on his forehead and tried to use his chakra to make the leaf stick to it. His first try the leaf barely sticked to his forehead for three seconds before falling. By his fifth try it stayed for a minute, by his tenth try it got to ten minutes and by his twelfth try he basically had enough control to try the next exercise.
Hiruzen, who was watching all this shocked to the core. If you told him that after an hour that a five-year-old child finished the leaf concentration exercise in an hour he wouldn't believe you, especially if said child is a jinchuriki he would have asked you if you been drinking today.
But he was witnessing it right in front of him now. A child with jonin levels of chakra and being a jinchuriki has enough chakra control to begin the tree climbing exercise after an hour of practice.
Izuna was about run outside to begin the tree climbing but stopped when he felt Naruto looking at him curiously. He then stopped then explained to Naruto about importance of chakra control and the training method for it. He stayed and help watched over Naruto's training and gave advice where necessary and by Naruto's tenth try he got it down.
After that they then went to a training ground to do the tree climbing and water walking exercise. Hizuzen was a bit curious seeing how fast they quickly they completed the exercise followed them.
It took them about only about ten minutes complete.
After completing his training, Izuna then reviewed it.
'The Training methods aren't bad, the more you do them the better your control gets. Even if you have mastered the method, the more you use it the better your control gets. Even so I prefer my method just consciously flowing your chakra though your pathways can help you with control chakra much easier and faster.' Izuna mussed to himself before turn to Hiruzen to ask for his opinion.
Hiruzen quickly got out of his shock the twins gave him and began to listen to what Izuna is talking about. He pondered a bit before giving his response. "Tsunade already came up with a method that is similar. She would slowly fill up her seal with chakra that is on her forehead. Out of everyone I know she is the closest one to having perfect chakra control so I would say that your method is pretty good."
'Might try it myself.' The Hokage thought to himself.
Izuna didn't really care who Tsunade was and just nodded. After getting the Hokage's approval he went to teach Naruto the new method. He then spent two hours instructing Naruto.
After they completed their training, they return back to the hokage mansion where they set aside an hour a day for chakra control training.