Whumptober 2019, Alt. Prompt #5: "Fist Fight"

When Hosea and Dutch had taken Arthur in, he had been fifteen, but he'd looked to be no older than twelve.

They'd thought he was lying when he'd said he was 'around fifteen, I'm not sure.' He couldn't remember his birthday, but it had been around six years since his pa had been hanged and he'd moved out onto the street, and they had decided that he was fifteen and his birthday was the day he joined their little family.

They'd noticed him growing healthier.

His scrawny face had filled out, no longer skin on bone, his blue eyes more clear than before. But over the years he'd always seemed to still be the little boy, still short and scrawny, even as he helped them rob banks, steal from carriages and trains.

He was nineteen before they realized just how big he'd grown.

No one was quite sure how the brawl had started.

Maybe someone caught Dutch flirting with their wife, or Hosea got caught pick-pocketing. Or maybe Arthur sent a prostitute away just a bit too rudely. But one minute it had been nice and calm, and the next the saloon had exploded into chaos. A man had been swinging at Hosea, another at Arthur, and someone had been throwing a chair at Dutch. ("A chair Hosea, can you believe it?!" "Yes, Dutch, I can.")

Arthur had been lost in the chaos, but the saloon had cleared out quickly, Hosea slamming the butt of his revolver into his opponent's temple, and he couldn't see what Arthur had done but his opponent laid still on the ground and, as Dutch's grabbed him by the collar of his shirt and slammed him into the wall, he charged across the saloon, body thrumming with adrenaline.

"Arthur!" Hosea cried in panic as the boy, no, man, grabbed him by the back of his shirt and twisted, yanking him completely off of his feet and throwing him clear across the room.

"Arthur?" the pair gasped—when had he became able to do that. But the man was trying to get to his feet, and so Arthur lunged after him, dropping to his knees to straddle him, grabbing him by the collar of his shirt and slamming his fist, over and over, into his face with an awful crunch crunch crunch, shattering his nose, the man thrashing to try and free himself.

"You alright, Dutch?" Hosea asked, approaching the man who was trying to put himself back together, both of them keeping an eye on Arthur,

"I'm alright-Jesus!" he hissed at a particularly harsh blow, Hosea flinching.

The man twisted, braced his foot against Arthur's stomach and kicked, sent him staggering back and onto his feet with a grunt. He hurried after him, lunging forward and striking Arthur in the face with a painful right-hook, sending him stumbling.

Dutch hissed, moving to intercept, but Hosea grabbed his shoulder and said "Dutch, wait."

Arthur caught himself, using the momentum to surge forward, hitting the man so hard his head snapped back, stepping forward again and landing another blow, grabbing him by the collar of his shirt, effortlessly lifting him up and throwing him into the wall behind the bar, the bottles of liquor shattering so loudly they cringed. The man crashed to the ground and lay still.

Arthur stepped back, panting, before turning to look at Dutch, and for the first time in years they really saw him. He was well over two feet taller than he'd been when they'd taken him in, they'd be willing to bet, and as he approached Dutch realized they were just about eye to eye, and Hosea had to tilt his head back to meet his gaze. Arthur was incredibly broad, a shire where he'd been a scrawny arabian foal before, all thick muscle, no longer knobby-kneed.

When had he grown so tall?

When had he grown so strong?

When had their boy grown into a man?