This story is set a few months after The Guiding Winds, my Anakin survives ROTJ AU. You don't necessarily need to read that one first, but it may give you a better feel for Luke and Anakin's relationship.

I'm stealing the title for this from the Puscifer song The Humbling River, which is probably one of the best songs for this father-son relationship ever.

Nature Nurture Heaven and Home

"But this doesn't make any sense!" Luke said, tossing the datapad onto the small table with a huff and sinking back against the sofa cushions.

From the other side of the room, his father chuckled, but he didn't raise his eyes from the pile of parts spread across the table in front of him. Something sparked, and Luke looked up sharply in time to catch Anakin frowning in frustration at the hydrospanner in his hand.

Artoo beeped and whirred, sounding caught between worry and amusement.

"Yes, yes, I know," Anakin grumbled. "That's not going to work. You don't have to rub it in."

Artoo let out a rapid series of whistles that sounded like nothing so much as guffawing laughter. Luke grinned. After a moment, Anakin's frown slipped, and he laughed.

Luke felt his own smile soften. He didn't think he would ever get used to hearing his father laugh. It was new and strange and wonderful every time.

"Fine," said Anakin, dropping the hydrospanner on top of the haphazard pile of parts. "I'll take a break. Probably going to have to modify the design, anyway." He stood and stretched with a sound of popping joints and faintly whirring gears, and the respirator briefly picked up before falling back into its usual rhythm.

"What are you working on, anyway?" asked Luke, but without much hope. Anakin had refused to tell him so far, and now seemed to be of the opinion that if Luke couldn't figure it out on his own from watching his father work, he didn't deserve to know.

"Nothing that concerns you," said Anakin with a wry twist of his mouth. "But you can tell me what has you so frustrated, son."

Luke sighed, glancing at the datapad but not picking it up again. "I've been reading through the old Jedi records," he admitted, half-apologetically. As he'd expected, his father stiffened, and Luke almost decided to drop it.

"And?" said Anakin, his voice flat and far too steady.

Luke eyed him closely. They didn't often talk about the Jedi, really, and there were a lot of reasons for that. But maybe…maybe they should.

"A Jedi shouldn't love," said Luke, looking anywhere but at his father's face. "That's what it says. But that doesn't make any sense. How can we ever be – " What was it Ben Kenobi had said, so long ago now, when Luke was a different person? " – the guardians of peace and justice in the galaxy, if we don't show compassion? That's – that's the most important thing. And isn't compassion just unconditional love?"

To his great surprise, Anakin burst out laughing.

Luke's gaze snapped up from the table and he stared at his father.

"I said the very same thing to your mother, once," Anakin said, his laughter softening into a wistful smile, but his eyes still sparkled with mischief. "She thought I was flirting."

Luke laughed. "Were you?" he asked slyly.

Anakin's smile grew. "Maybe," he said. And then he sighed, coming to sit beside Luke on the sofa. "But I meant it, too."

Anakin Skywalker was a big man. Not quite so massive now, without the armored life support system he'd worn for twenty years, but he still towered over Luke, even sitting down. Sometimes, Luke thought, he tried to make up for it, as he was doing now: sitting very still, his shoulders hunched downward, self-contained and trying to make himself as small as possible. Luke didn't think it was even a conscious action. He'd grown up on Tatooine, too, not a slave, but always the freeborn son of a slave, and he knew what that impulse meant in his father. It was something older than the Sith or the Jedi.

Pass on what you have learned, Master Yoda had said. And Luke had been thinking about that a lot. Pass on what he'd learned. But Yoda had never specified which things.

"Well," Luke told his father, bumping their shoulders together and offering a grin, "I think you were right."

Anakin seemed to relax subtly, the stiffness going out of his spine, his shoulders opening up just slightly. "You proved me right," he said, with all the hushed reverence of a confession.

Luke offered a confession of his own. "Yoda told me to pass on what I've learned," he whispered. "I think he meant – he meant the Jedi teachings. But that's not all I've learned." He looked up at his father. "It might not even be the most important thing."

"Then you should pass on what's important, son," Anakin said softly. "You're wise enough to know what that is." He snorted quietly. "Wiser than me."

"I don't know about that," said Luke, bumping his father's shoulder again. "I think we should do it together."

"I'm not sure I know how," Anakin admitted, staring down at his hands. "But – " He hesitated a moment, but when he looked back up at Luke, there was a strange, almost hopeful determination in his eyes. "But I could learn, maybe. I couldn't learn before, but I could from you." His mouth twisted in a sudden teasing smile. "I'll be a Jedi like my son before me."

Luke blinked, then threw his head back and laughed. They could do this. They really could. And it was everything he'd ever wanted and never truly hoped he could have. His father, his sister, his friends, the galaxy free and open and full of possibilities. And love. Unconditional love.

"All right," he told his father. "We'll figure it out together."