A/N:This is another fic centering around Lightning and Serah, but it's not something romantic, just family. It's post-game so there are some spoilers, just warning you now. I originally intended for this to be a oneshot, but I ended up splitting it into four parts. I feel like I jumped all over the place but in any case, here's the first chapter.

-Chapter 1-

Lightning Farron was sitting in the waiting room of a makeshift hospital in Oerba. The walls were made of metal, and the chairs were made of hardy wood. There were some people sitting near the walls, holding some injured body parts, and masks covering their faces. All of the Cocoon residents had to get used to life on Pulse and create new buildings to live in, but the hospital was one of the first places up and running. Gran Pulse was a dangerous place swarming with fiends and Behemoths, so people had to learn to fight and defend themselves. Of course, not all of them had the training so injuries were expected for the first couple of days. That was why the hospital was set-up, because, who knew what else lurked out there? People wanted to be very sure that they would be able to recover with whatever that would come their way. But this was all beside the point. Lightning was thinking about what had transpired in the last few days, and her thoughts fell on her little sister, Serah.

Lightning simply didn't understand. Why her of all people? It had been merely a week since Serah had come out of her crystal stasis. A week since Vanille and Fang gave their lives to save Cocoon. A week since all Cocoon residents moved to Pulse. Even after everything she had done to save her, Serah was dying. Practically a day after she came out of crystallization, she had a heart attack. The doctors said it was an unknown side effect of waking up from crystal stasis. As a better example, it would be like being frozen in cryogenics. If you forcibly awaken someone from their icy slumber, the body can't handle starting all functions immediately. Thus, to forcibly awaken someone would damage the person, without any hope of recovery. Lightning and the others were fine because they hadn't been in crystal stasis long. But Serah… it had been a long time for her.

Sarah eventually woke up three days later, saying that she was fine. The doctors came into the room with soft smiles, but Lightning knew better. As soon as she left the room, the doctors pulled her aside and told Lightning that there was no possible hope of recovery, even with their advanced medical technology. They never had a L'Cie who completed their focus, come back before, so there was no known way to treat her. Other than her heart, there was nothing physically wrong with her. Because her heart couldn't pump the necessary blood for her normal bodily functions, the doctors estimated that she would live a few more months, before her heart simply couldn't provide the necessary blood anymore. They told Serah shortly after, and she was hardly ecstatic at the news.

Lightning then recalled the words the doctor had told her ten minutes earlier, "The only way to save her is through a heart transplant."

Heart donors were hard to come by, because, if one gave up their heart, they would obviously die. It was hard to imagine giving up your heart to someone you know, let alone a complete stranger. The chances were even slimmer now than ever, because everyone was trying to adjust to life on Pulse. People didn't have any Fal'Cie to rely on, so they had to do everything for themselves.

Serah was too young to go like this. She was eighteen for god's sake. She didn't deserve this, she had so much to live for, she had her engagement with Snow, her college years, her first child. But what did Lightning have to look forward to? The only thing she had ever known was her job in the military and protecting her sister. Originally to find Serah, she quit her job in the military. After the whole L'Cie mess was over, Lightning decided to spend more time with her sister. She had to make up for the several years of letting Serah feel lonely, so she opted not to get her old job position back. That was the main reason of the two's isolation to begin with. In addition, she was soon going to lose her sister again soon. She would once again after to face her younger sibling, dead. This wasn't something she could bear to see again. She had to do something but what? What could she even do? Then she understood.

She would give her heart--- for Serah's sake.