Minato sat in the waiting room of the secluded medic-nin office. Lately, Kushina hadn't been feeling too good, so he pulled some strings to get Konoha's best medic to give her a checkup. It started with her slowing down and punching with less power in their spars, but recently, Kushina had said she was starting to get headaches. He was worried for her, as Kushina is too stubborn to admit that something is hurting or bothering her.

"Minato"

Minato looked up at the sound of his name to see Tsunade had exited the medical room. He did not like the grim look on her face. "Is she alright?" He asked.

"She's fine right now. There is some good news and some bad news." Tsunade said gravely.

Minato's heart plummeted straight down to his stomach. Judging by Tsunade's tone, the bad outweighs the good. By a lot. He nodded stiffly, "Good news first."

A small smile reached Tsunade's face, "The good news, is that you are going to be a father."

Minato's soul was instantly lifted in love and joy before depressing in bitter sweet emotion. He was definitely not going to like what came next.

Tsunade took a deep breath, "The bad news is that the Kyuubi's chakra is slowly poisoning her. The little bits of demon chakra that come from the seal are building up her chakra toxicity until her body can't handle it anymore. Normally, her reserves would filter it out, but the constant outflow from the Kyuubi is preventing her system from filtering it. With the rate that the chakra is leaking from the seal, it is likely that she will die with her child's birth."

Minato was stunned, but within a moment the sealing possibilities started running through his head. A chakra storage seal won't work, and neither will reinforcing her seal. The outflow of chakra from a seal is unpreventable, otherwise it will stop working. Adding more chakra to her system to help it filter the bijuu chakra won't work because of her special Uzumaki chakra and the lack of Uzumaki. Sealing the Kyuubi into another person won't work either due to the stress on her chakra system from moving it out of of her body. His thoughts went to his unborn child. That's it! If the Kyuubi is transferred into the child, then it won't be leaving Kushina's body and therefore won't stress her chakra coils as much! The only problem is that the unborn child won't be able to handle all of the Kyuubi's chakra. I need more information about this. Minato immediately snapped out of his frozen state and raced off to the Konoha archives.

Tsunade simply stared after him. He had taken that a lot better than she thought he would.

Konoha Shinobi Library

Minato entered the library at a brisk walk that anyone else would call running. "Inu, find me all the books on chakra coils and systems. Hawk, find me any information on pregnancy and fetuses. Tora, gather all of Mito Uzumaki's journals, writings, and diaries that have anything to do with the Kyuubi, Jinchuriki, or the Bijuu. Go."

While his personal ANBU guard went to fetch the things he requested, he went to the hidden place in the library where he kept all of the high level sealing materials and seal testing rooms. The first thing he did was go through Orochimaru's sealing notes and ideas. Although Orochimaru left the village after being caught doing immoral experiments on infants and civilians, he couldn't deny the skill Orochimaru had with both genetic and chakra modification seals. Take the cursed seal he put on little Anko for example. It was structured to make the maximum use of the energy generated by negative emotions by converting it into chakra that is split between giving the user a chakra boost and fueling a secondary part of the seal that changes the user's cell structure to reach peak efficiency. At least, that is what Minato understood of it. That area of sealing wasn't his specialty.

Rummaging through Orochimaru's notes he soon found a paper about recreating the effects of a bijuu's chakra to allow shinobi to have a last resort to make them stronger. Scanning the paper he saw that most of it was about how to make demon-like chakra and store it. He scowled. This isn't very useful. Something caught his eye at the very end of Orochimaru's shelf of notes. The notes were in a small book instead of being scrawled on paper like most of them. Picking up the notebook, he read the title written on the front in Orochimaru's handwriting.

Transferring Chakra-Based Bloodlines During Infancy. He assumed by the book's location at the end of the shelf that it was the last book of sealing notes he wrote before his exile from Konoha. Unless there is a secret laboratory that ANBU hadn't found yet with a more recent one. Opening to the first page, he began reading.

I have recently made a breakthrough in my research with chakra-based bloodlines. I realised through much experimentation that recreating the Wood Release bloodline through genetic alteration has failed so I started looking at the possibility that Bloodlines are formed through unique chakra systems. The way the chakra system forms during pregnancy allows the child to mold chakra better in certain ways. This is where I hypothesise bloodlines like Wood, Dust, and Ice release come from. Chakra systems solidify 24-56 hours after birth, which is the reason why bijuu can only be sealed into newborn children. After the chakra system solidifies, minor changes can be made to the system up until age 12-13, but they will experience drawbacks. After age 12-13, the chakra system is fully developed and attempted changes will kill or permanently cripple the subject.

The rest of the page was filled with sketched diagrams of chakra systems at different ages. Flipping to the next page, Minato continued to read.

My current experiment with Wood Release is exposing a child's chakra system to wood natured chakra in the womb, where their chakra system is still forming. This will force the unborn child's chakra system to adapt to that nature of chakra and therefore allow the child to mold chakra of that nature. The problem with this method is that a constant flow of the natured chakra needs to be flowing through the system in order for it to retain the capabilities of chakra molding. The natured chakra is not needed after the solidification of the chakra system, as it will then retain it's shape. This method could also hypothetically be used to birth shinobi with extremely strong elemental chakra natures, possibly mix elemental chakra natures to create an artificial bloodline, allow shinobi to produce demon chakra, or create seamless jinchuriki that can use bijuu chakra without it corrupting their emotions or chakra systems.

Minato dropped the book and immediately left the room. He had his solution. What he didn't notice, was a small white snake summon take advantage of Minato's carelessness in leaving the door open to dispose of Orochimaru's notes and projects.

What he didn't notice, was the next page of the notebook, that spoke of the potential side effects of changing a child's chakra system during pregnancy.

Hokage's Office

"Inu, Hawk, Tora" Minato said as he summoned a couple of clones to grab the stacks of paperwork on the desk and work on it elsewhere. The ANBU instantly appeared and Minato nodded at each of them. "Have you found the materials I requested?" Minato asked, and the ANBU simply responded by each of them pulling out a large stack of books and papers. Minato almost cowered but thought of his wife who has less than a year left to live if he can't find a way to transfer the Kyuubi's chakra to his unborn child.

Namikaze Estate: 2 weeks later

Kushina was beyond pissed at her husband. She just found out that it was likely she wouldn't live past her son's birth and she hasn't even seen Minato, much less spend her remaining days with him! Although the doctors said that they can't tell the child's gender at this point in time, she knew that she was having a son, believe it! Kushina's eyes started watering for the millionth time in the past couple weeks. I won't be able to watch my son grow up. Not his first steps, first jutsu, first love… Kushina quickly rubbed away her tears with her sleeve. All her sadness was then immediately replaced with fury. How dare he! Minato hadn't talked to her once about all this and kept himself locked away in the Hokage's office while she cried here alone.

"Kushina!" Minato yelled as he used his flying thunder god jutsu to appear inside the house.

Kushina was seeing red though. Does her husband think he can just waltz in and act like he always does when he knows she is going to die soon and hasn't seen her in 2 weeks. "Minato," Kushina began growling in a dangerous way that promised a lot of pain, "There had better have been a full on invasion for the past 2 weeks to excuse this. Talk."

Minato was instantly talking to save his hide from a frighteningly angry Kushina, "Worse than an invasion darling. When I found out about the problem that you were having I couldn't just let you die without trying to find a solution. I've been working 2 weeks straight to ensure your safety, love."

The red faded away from Kushina's vision and she saw how tired Minato looked. It looked like he didn't sleep at all for at least a week and only ate and drank the bare minimum to survive. Then despite his exhausted state, he used the flying thunder god jutsu to get back to her as fast as possible. She thought it was quite sweet.

"Alright," She said and kissed her husband on the cheek, "You're forgiven, believe it."

Minato sighed in relief and said, "Well I found an answer. Basically, I'm going to make a seal that slowly transfers the Kyuubi into our child. Our child will never have the same problem you have because it's system will build itself in a way that can naturally accommodate it. By the time our child is born, it will hold the entire Kyuubi."

Kushina blinked. She didn't understand most of that so she did the only thing an Uzumaki mother would do in this situation.

"Stupid. Don't call our son an it! Our baby is going to be a boy, believe it!" Kushina yelled at him.

Minato chuckled, "Okay then, we will do the sealing in 2 days."

Kushina looked at him a little oddly. "But won't whatever you work best if it's done as soon as possible?"

Now Minato was laughing in a way that was only possible if he was a least a little insane, "That is as soon as possible, I can barely stand right now."

Kushina didn't have time to respond before Minato fainted on the spot. Using her superior ninja speed she caught him and brought him upstairs to lay him in their bed. Brushing a few of Minato's bangs to the side, she put a gentle kiss on his forehead. Her husband was going to be absolutely pampered during the next couple days, believe it!

Namikaze Sealing Room: 2 days later

After receiving the best treatment from his wife while he recovered, Minato began writing the seal array over every inch of Kushina's body. Kushina and Minato were comfortable with each others bodies, so Kushina had no problem stripping while Minato scrawled advanced seals all over her body. She had more of a problem refraining from teasing her husband while his sealing formula started covering… more sensitive areas.

"This is kinky," Kushina said, "The Uzumaki did a lot with seals, but I never thought of using them in foreplay." She wriggled her eyebrows at Minato while he blushed.

Minato stayed mostly professional as he finished writing over the difficult areas and worked towards the seal on her stomach, where the most important parts of the array would be making sure that the Kyuubi didn't escape or damage Kushina's chakra system. He also had pills with seals written in water and acid resistant ink that Kushina had to take throughout the course of her pregnancy. These new ingestible seals made sure that the Kyuubi wouldn't escape from 'Naruto' as Kushina had taken to calling their son. Minato finished the array and disguised the seal with the kanji for 'child'.

"Are you ready Kushina? I'm going to activate the seal." Minato said as he completed the seal.

Kushina nodded. "I'm ready Minato."

Minato clapped his hands together before saying, "Sealing Arts: Seal of Sun and Moon, activate!". Minato then sent his chakra through the seal to activate it.

Kushina's eyebrow twitched, "Minato, that didn't do anything."

Minato shook his head, "No, it did work. Remember that this is a seal that is transferring the Kyuubi's chakra into Naruto over the course of your entire pregnancy. It won't transfer it all at once."

Kushina stood up and gave Minato a hug in her full naked glory, "I love you so much and I am so glad that I will be able to raise our son with you, believe it."

"Yeah," Minato said as he hugged her back, "Me too."

Tsunade's Office: a few months later

Green medical chakra covered hands hovered over one Kushina Uzumaki's stomach. Tsunade frowned before turning to Minato. "The Kyuubi's chakra is interfering with my diagnostic jutsu, so I can't tell you any details about the baby, but I can tell you 2 things. The baby is healthy, and it's a boy. Aside from that, Kushina's condition now shows no signs of deteriorating."

Kushina couldn't care whatsoever. Her baby Naruto was growing and she would be able to see him soon. She launched herself at Minato and glomped him. "Isn't this great! Soon we'll be able to see Naruto with his first toys, first teeth, first solid food, first drawing…" Kushina continued gushing to Minato.

His mind was filled with darker thoughts though. If Tsunade's diagnostic jutsu couldn't detect much around the Kyuubi's chakra, how do they know something didn't go wrong with the sealing? What if Naruto was born with a ruined chakra system? Or if he was sickly and weak due to the huge contrast between his chakra amount and physical body? He tuned back into Kushina's drone just as she finished.

"-and we'll both be able to teach him how to be the best ninja ever! Believe it!"

Minato smiled at his wife's cute verbal quirk and wondered if his son would pick it up as well, "Sure, I believe it."

In a doctor's office just outside Konoha: some months later

A couple weeks after that last checkup with Tsunade, her lover had died. She was gone from Konoha by the end of the funeral, and Minato couldn't stop her. He did manage to convince her, with over a month of persistent letters, to help with Naruto's birth. That was where they were now.

"Come on Kushina," Tsunade said over the muffled groans and screams from Kushina, "One more push."

Kushina was sweating heavily from the effort. This was more painful than anything she's experienced in her career as a ninja. Although that may have been more because of Minato than anything else. Kushina did not linger on that thought as it only served to belittle herself as a ninja. She weathered through a final contraction before the extreme pain was replaced by a dull ache. Multiple gasps were heard in the private doctor's office.

"Tsunade," Kushina croaked out with her voice rough from her yelling, "Let me hold him."

Tsunade seemed slightly reluctant for a moment before complying with her demands. Kushina wrapped her arms around her newborn child as she began to doze. She wrapped her arms around her son, and all nine of his swaying fox tails.