A/N: Now I wouldn't say that Rena Hatake is me in the Naruto universe, but I would like to think she's one of my friends who shares at least some interests as me. Such as books or maybe fashion tastes.

Also I intend this series to be a mix of light-hearted scenes to serious ones. I think this way it shows moments how Rena and Kakashi develop their relationships and personalities.

Rena is about 9 and genin Kakashi is about 13 and jonin but not yet ANBU. Post Shinobi War.

It was one of those rare days Kakashi and Rena weren't needed on any missions. The siblings had partially opened the curtains and windows letting rays of sunshine and light cool breezes. The day had been really relaxing and peaceful; the Hatake siblings could finally enjoy time to their selves; Rena and her reading, Kakashi and his, well, reading. They were shinobi geniuses and they loved their books.

Rena had been sitting on the end of the couch, casually reading the Woman Warrior. Kakashi had just finished up washing and putting back all the dishes from lunch. He couldn't wait to dive into a book of his own. It must have been a very serious book judging by the cover and thickness, but Kakashi never allowed Rena near it. It was called 50 Shades of Darkness or Grey, one or the other.

As Kakashi walked into the living room from the kitchen, the collection of family photos gathered his attention. 3 photos were placed in a straight line from oldest to newest, each one displaying the Hatake family. However, each picture was significantly different. The first photo showed Sakumo holding an infant, wrapped in a baby blue blanket, in his arms while sitting next to his late wife; both parents looked very happy. The second photo only contained a slightly older, slightly sadder, and more tired Sakumo holding a 2-year old Kakashi. The third and most recent photo captured an even sadder and even older Sakumo holding a bundle wrapped in baby pink while sitting next to a 4-year old Kakashi; Kakashi had his signature mask on by now.

She must've known for some time now. Her illegitimacy had been the talk of the town at one point. Perhaps it's time to tell Rena the truth about her lineage. Kakashi may have never met his mother, but at least he had the picture his father had kept; he knew what she looked like. However, Rena's mother on the other hand, was a complete mystery. Even Sakumo never spoke of her.

Kakashi sat down on the opposite end of the couch and stared at his sister. They certainly looked like siblings who both took after their father; no one would have ever guess Rena was only Kakashi's half sister. If it weren't for the gossip, that is.

Well, I guess now is a better time than any other. I hope she's ready for this.

"Rena, there's something I gotta tell you." Kakashi was nervous.

"hmm? What's up?" Rena sank in as much information from that page as fast as she could before creating a doggy ear and placing the book in her lap. She looked over at her brother. To Rena, Kakashi was acting as weird as ever. For starters, he was all the way over at the other end of the couch.

Kakashi debated if he should sit closer to his sister or not. He decided against it and awkwardly leaned against the arm rest while trying to face his body towards hers.

"Uh. I don't know how to say this but.. uhm you know our father.. Uh well he- uhm. You know our mom? or rather.." Damn. Kakashi shouldn't have spoken without planning what to say first. How exactly do you bring up to your half sister that you don't share the same mother?

"Is this about our parents?" Rena already knew where he was going with this conversation. It only took a Hatake genius, which she was, to figure it out. To figure it all out.

Kakashi shifted positions "Yeah.. it is."

Rena smirked, "Is this about who my real mother is?"

Kakashi gaped at her response, "uh... what?!"

For a prodigy, Kakashi could be a real idiot when it came to his sister. "Well the first thing that threw me off were the family photos. And then I noticed your mother's grave stated she died before I was even born, let alone conceived." Rena paused before going on, "Plus you know what the villagers have been saying, right?"

Kakashi's surprised expression slowly changed; he looked down at his feet. "Yeah, I've heard."

She studied her brother not sure what he would say next. "Are you going to tell me who my real mother is?"

Kakashi was speechless. He didn't know what else to say. She had hit the nail right on the head. But one thing bothered him, he didn't know who her real mother was. Only their father, a specialized doctor, and the Hokage knew. And apparently his lack of a response showed on his face.

There was a small silence between the siblings.

Rena spoke first, barely above a whisper, "You don't know.." She was disappointed. When this conversation started, she had hoped she would get answers about her lineage.

Another small silence.

"I know who knows though." Kakashi stared at the floor. The last thing he wanted was to disappoint his sister, and although what he said may have been false hope, it was worth a try. At least just for her. He eyed her from the corner of his eyes and gave him a side smile. Needless to say, they were out the door in less than a minute.

-In The Hokage's Office-

"Minato-sensei, I have a favor to ask you." Kakashi and Rena were standing side by side in front of the Hokage, with hopeful looks on their faces.

"It's Hokage-sama, Kakashi. But what can I do for you?" It was interesting. Very. Interesting. Kakashi and Rena in the hokage's office together? Not regarding a mission? This was a sight to see.

Maybe things are looking better for Kakashi. Minato silently hoped.

"We need access to Rena's birth records." Now this was definitely interesting, and shocking.

Minato had forgot ten all about it. He skimmed through it once during his early stage as Hokage but it quickly left his mind. The Hatake siblings were only half siblings. But was it really okay for them to access those files? Sakumo had never left a thorough will, only stating that anything that had belonged to him now belongs to his two children. And said children hadn't even reach the age of 18, or 16. One was barely 10 years old! However, they have taken good care of their selves and each other. Minato decided these files weren't as harmful as other events in these kids' lives. So down to Intel they went.

He ordered a near by ANBU to retrieve all files on Hatake Sakumo, Hatake Rena, and Hatake Kakashi. Of course, Rena's file only consisted of a small folder, while Kakashi had his own container and their father had several, several containers. Thankfully, everything was sorted by date.

It wasn't that much of a shocker Rena's files didn't contain anything regarding her birth or her parents, no one had known Sakumo even had a second child until the villagers watched Rena grow up with the signature Hatake silver hair; she was practically a ghost. But what was disappointing to the trio, was that not even Sakumo's files contained any information. They had checked the year before, during, and after Rena's birthday, and still found nothing. Minato was perplexed, he could have sworn he read Rena's birth certificate. He watched the saddened faces on his student and his student's sister. The Hatake siblings, they're going to be a force to be reckoned with.

"Alright, lets check Kakashi's file." Minato smiled confidently. If it hadn't been in their father's file then it certainly was in Kakashi's, he was sure of it.

"Are you sure that's a good idea sensei?" Kakashi silently gestured towards his sister who was sitting right next to time.

Minato chuckled, "I have a good feeling about this Kakashi. Rena, when is your birthday?" Rena hadn't paid any attention to the two older males, until she heard her name. She was too busy admiring the different pictures of her father. They weren't the same as the ones Kakashi kept at home.

"Rena."

"Oh uh April 2nd." Minato went straight to the file in the container containing the year Rena was born, and sure enough there was a file under April 2nd. The file was thin and labeled 'Kakashi Gains a Sibling'. Bingo! They found it!

If Rena was being honest, she was both excited and terrified at the same time. She was scared to find out who her real mother is. What if her mother had been a bad person? Would that mean Rena would turn out just as bad?

To Rena, Minato could not have moved any slower pulling out her birth certificate. She wanted to get this nerve racking experience over with. She wanted to settle all this information as fast as possible, not have linger in the air around her. Minato finally read the birth certificate out loud.

"Father: Hatake Sakumo. Mother: Amaterasu Kushinada" Minato reread Rena's mother's name over and over again in his mind. Did he recognize her? He didn't but the name felt familiar.

"I think, that's the sister of one of the men my father saved during.. that mission." Kakashi spoke softly. He wasn't entirely sure, but that last name definitely stuck in the back of his mind.

Rena was still quiet. She silently studied the birth certificate, "How did she pass away?"

Kakashi and Minato both took a breath in. Well, she's moving fast.

Minato didn't know how to deliver the next move. He regretted to say "Rena, your mother... passed away during child birth." He stared at her worried what she would do next. She expected it of course, but she was still somewhat shocked. Rena didn't know what to do, should she be satisfied? Or was there more about her mother she might want to know?

Kakashi handed her a picture of Amaterasu Kaguya to Rena. Kaguya was an ordinary woman, but she was also very pretty. Her brunette hair was long enough to reach her thighs. In this picture Kaguya had worn a baby pink kimono decorated with sakura flowers with light green accents. Rena didn't know what she felt as she stared at the picture. She finally saw how her mother looked.

Kakashi patted and rubbed Rena's shoulder, like he would do when he knew she needed some comfort. "What do you think? How does she look?"

"She's pretty.. really pretty."

A/N: What did you think? Please leave reviews so I know how I'm doing :)