I'm too busy crying over Fullmetal to own it
"Dad, before you and Brother go, would you tell me about Xerxes?" Alphonse asked quietly from inside the large dome he had sealed himself in order to contain the homunculus Pride. On the other side, Hohenheim visibly started at the question while Ed merely stared at the earthen wall that separated him from his brother, trying to guess what he was thinking. Ed had to admit he too was curious about the revelation of Hohenheim's origins. From what he'd heard, Xerxes had been a thriving country, rich in culture and knowledge until it had been wiped from the Earth by a tragic transmutation. Edward lowered his eyes to the ground, but on the other hand, if it weren't for that transmutation neither he nor Al would be here right now. "I mean I know this isn't the best time and you have to go but… We just got you back and who knows how long I'll be in here. Just tell me something, anything, to keep me occupied."
Edward rested his flesh hand against the barrier, once again angry that he had to leave his baby brother stranded with a monster for God knows how long. He glanced over at Hohenheim and gave him a curt, reluctant nod. Bastard or not, Hohenheim was still their father and if stories from his ancient past gave Al some peace in this unfair situation then Ed was all for it. Hohenheim gave him a small sad smile before turning his eyes toward the sky remaining silent for a few moments before speaking softly.
"I wish you boys could have seen it, it was absolutely beautiful. It had its bad parts like every other country. Slavery was still commonly practiced, I myself being born a nameless slave and there were the people who willingly destroyed human lives to create the transmutation circle." Hohenheim closed his eyes, "But even though it's been so many long years I can still picture the way the sun sparkled on the sand in the early morning, how the glistening white buildings shone like a great beacon of hope. Alchemy was, as far as I can tell, initially discovered by the Xerxesians and during my training I read so many hemp scrolls that dated back centuries. It was a city built upon the knowledge of many years while still looking towards the future with a culture and people unlike anything else. It really was the jewel of the desert, a true paradise on Earth." He sighed wearily and rested his forehead against the wall. "But it's all gone now," he whispered quietly sounding like he was about to start crying again.
Edward looked away uncomfortably. Hohenheim was far too emotional for him, but again, maybe if Ed had seen his entire culture wiped out in front of him he would be emotional too. He heard some shuffling from inside the dome and soon he heard Alphonse knocking supportively from his side. Hohenheim chuckled warmly and gave a friendly knock back. He looked over at Edward and with one hand beckoned him closer. Ed shifted, torn between his stubborn desire to hate Hohenheim for leaving them and his understanding as to why he had to. Hadn't he and Al, after all, done the same thing to Granny and Winry? He finally relented seeing the sad, hopeful face his father wore. He grumbled as he awkwardly shimmied over until he was just barely within reach, so that was where Al got his guilt inducing abilities from.
"I had lived for so long without friend or family; I wandered for years without purpose, doing nothing meaningful because I was too afraid of getting attached because I knew it would only mean another goodbye." Hohenheim finally reached out and pulled Edward towards him. There was still a distance between them, but Ed secretly at the very bottom of his heart admitted to liking the feeling of the warm hand on his left shoulder.
"But then I met Trisha, and she gave me you wonderful boys and I realized that the life I had lost wasn't completely gone. When I see you two, I see the new beginning of a beautiful culture long gone, not just in your hair and eyes but in your hearts. People of the desert are strong and stubborn and capable of great things. And for what it matters, your mother and I have always loved you and we are so proud of you both, no matter what's happened in the past. I know wherever she is, she's smiling on you right now." Ed's pursed his lips as he heard Al make a sad choking sound on the other side and he gripped his automail arm tightly. The guilt he felt over the failed transmutation had haunted him for years, and to think that his mother would forgive him...
"Dad," Al replied hoarsely, "after this is done? Are you going to stay with us?" Hohenheim stroked Edward's shoulder which broke the younger boy out of his painful reverie. Ed instinctively recoiled, pulling away from the man who only now pretending to be a father after so long away. He ground his teeth as he protectively refolded his arms over his chest, angry at himself that he was being comforted by this bastard who had long ago lost the right to care. He turned his head away to avoid Hohenheim's dejected gaze.
"I don't know Alphonse; I never was a proper father to you boys. Because of my actions you had to go through such hardship but at least you didn't have to do it alone. You built yourself a good support group and you not only survived but you've thrived. The way I see it, you don't really need this old failure of a father around anymore." He looked like he wanted to reach out to Edward again but pulled his hand back. "But it's up to you boys, you're all I have left now that Trisha is gone, I'll be there however you want me to be." Edward snorted and turned to address Hohenheim.
"Well you're right about one thing you bastard, we don't need you. Al and I grew up without you and no amount of dumb words or stupid gestures is going to change the fact that you were a shitty father." Edward said harshly, doing nothing to reign in the spite in his voice. "If it were up to me, I'd like to never see your dumb face ever again!"
"Brother!" Alphonse chastised and Edward took a deep breath before breathing out through clenched teeth, fiddling with his fingers as he began drawing circles in the dirt with his boot.
"But I guess if Al wants to have you around afterwards, then I guess I could put up with you. I mean Al's probably going to need help once he gets his body back and if you've got nowhere to go I'm sure Granny Pinako would take you in." Hohenheim laughed at that and lovingly patted the barrier between his youngest son.
"Well then I guess if I live through this then I'll be seeing you in a couple days Alphonse and I'll be able to shake your hand properly. I promise I'll tell you more stories about Xerxes later, but for now the sun's almost up and we really need to get going." Edward huffed and gave Hohenheim a light punch on the shoulder, well light by his standards anyway but Hohenheim merely gave him a watery smile which Ed ignored with a tight mouth and a blush. How did he ever end up with such a sappy old man?
"Of course you'll live through this you idiot bastard, you promised Al you would and I swear if you break another promise to my brother I'll resurrect your dead ass just so I can give it a good kicking." Hohenheim just smiled at him which only made Edward even more angry at the man.
"Alright, I'll do my best. After all, I've lived all this time doing nothing, why would I die now that I finally have something worth protecting? Now come on, we've got to prevent the tragedy of Xerxes being repeated here. Are you ready?" Edward rolled his eyes but gave his father a determined smirk, as close as he had ever come to smiling at him. It was quite an achievement for Hohenheim seeing his eldest son, so young and still so burdened, smile at him and it made him feel that maybe not all was lost. And when, days later, after the final victory had been achieved and he sat in front of Trisha's grave, it was that smirk and that comforting armored presence that he thought of. He whispered a word of thanks to a God he no longer believed in for that last chance to be with his sons.
He allowed himself one last smile as his soul began to slip away, Edward would be so upset with him. Once again he had broken a promise to his family as he expected his eldest would remind him of when he next saw him. But both he and his brother had bright futures ahead them, free from the strife of the past few years so. One day, the four of them would be together again but now as his last moments on Earth drew to a close, Hohenheim was satisfied.
This was something that upset me even back when I the manga came out monthly. Ed and Al are the last remnants of Xerxes, a totally dead culture and yet that fact is hardly ever touched upon! Not to mention that Hohenheim and his sons never really got the chance to know each other much less make-up for all that happened between them. So I did a short little insert scene around manga chapter 88 or episode 49 in Brotherhood. This may seem a little OOC for Edward, but knowing him I feel like he would've eventually forgiven Hohenheim for leaving them, especially considering why he did it. In my own happy headcanon, had Hohenheim lived, he and Edward would've had a distant but strong relationship. Also my beta was bored and couldn't bother reading it so if there's any mistakes, blame her.