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“Hah. UNO!”
Clark Kent declared triumphantly, slapping down a blue two with the self-satisfaction of someone who’d just saved the world and gotten a standing ovation for it.
John Stewart raised an unimpressed brow. “You realize that’s the first round you’ve won tonight.”
Barry Allen snorted as he drew another card. “I was starting to think Supes didn’t know the rules.”
Clark grinned and tossed down his final blue card. “UNO out.”
The Man of Steel stood up, did a little spin that vaguely resembled a victory dance, and nearly knocked over the plate of cookies with his cape. “Champion of the Fortress!” he declared proudly.
John gave him a deadpan look. “You’re insufferable.”
Barry laughed and reached for a cookie.
John began shuffling the deck again, precise and methodical. “Another round?”
Barry and Clark nodded, leaning back just as a blaring alarm began echoing through the Watchtower’s halls.
“Are we under attack?!” Barry jumped to his feet, ready to bolt into superspeed mode.
Clark tensed, already reaching for the communicator on his belt. “Bruce and J’onn are still off-world—how the hell are we supposed to defend the Watchtower without Batman?”
“We improvise,” John said, already heading for the command deck.
But before they could break into a sprint, a calm voice came over the system.
“Justice League members, stand down. There is no emergency. Please report to the command deck immediately.”
The tension snapped like a bowstring. The three heroes let out a collective breath.
“I swear I almost aged ten years,” Barry muttered.
Clark nodded in agreement.
They made their way to the main deck. The doors slid open, revealing J’onn, Diana, Alfred, and… a small child in J’onn’s arms.
“Uh…” John raised a brow. “Something you want to explain?”
J’onn exhaled. “Bruce and I were investigating anomalies on Planet Jaroz. We encountered a bioactive field of alien flora. It appears one of the plants had… temporal properties.”
He looked down at the child, who blinked up with stormy blue eyes and a deep frown.
“I got cursed,” the child mumbled.
Clark’s jaw dropped. “Wait—wait wait wait. This kid is Bruce?”
J’onn nodded slowly. “Yes. The same Bruce you once told me was ‘un-boopable.’”
Clark didn’t hesitate. He ran up, full big-brother energy, and gently pinched the kid’s cheeks. “Oh my god, look at this face. You are precious.”
Child-Bruce squirmed. “Cut it out.”
J’onn smirked. “Still hates affection. It’s definitely Bruce.”
“I—I thought maybe you adopted an alien child or something,” Clark stammered.
“Why would I randomly bring back a child?” J’onn asked, deadpan.
Diana and Alfred simultaneously facepalmed. Barry sighed. John looked like he aged another year.
“I’m not surprised anymore,” John muttered.
“I hate all of you,” mini-Bruce pouted.
Clark pointed dramatically. “Watch it, squirt.”
Bruce stuck out his tongue and blew a raspberry. Clark gasped like he’d been mortally wounded. “How dare you?!”
“Bruce,” J’onn said sternly. “Manners.”
The child crossed his arms. “Sowwy.”
Clark melted instantly. “It’s okay, buddy.”
Barry leaned forward. “How old is he like this?”
Alfred adjusted his glasses. “By Earth’s reckoning, about three.”
Diana cooed and pinched Bruce’s cheeks. “You’re adorable!”
Bruce slapped her hand away with shocking accuracy and twisted in J’onn’s arms like a cat who just spotted a bath.
J’onn sighed and set him down.
“How long does this last?” John asked.
Alfred shrugged. “The effects should be temporary. We retrieved a sample of the plant—it’s secured in the Batwing’s containment unit.”
J’onn, Diana, and Alfred headed for the hangar to examine the sample.
Barry watched them go, then turned to the others. “Okay… what do we do with this version of Batman?”
“I can babysit,” Clark offered. “I used to look after my nephews.”
“I’ll help,” Barry said. “As long as he doesn’t punch me again.”
“I’ll assist,” John added. “Someone needs to enforce order.”
They headed back to the lounge, with Bruce walking in slow, dramatic steps behind them.
Once there, they sat him between Clark and John. Barry set out snacks. Cards shuffled.
“Bruce,” John asked. “What do you remember?”
Bruce squinted in concentration. “Training. Diana. Fighting. Colors. That’s it.”
He proudly held up ten fingers.
“Why are you holding up ten?” Barry asked.
“I said ten things.”
“You said four,” John deadpanned.
Bruce blinked, looked at his fingers, and muttered, “…oh.”
Clark couldn’t help it—he laughed.
Hard.
Too hard.
Bruce sniffed once.
Then again.
Then the waterworks began.
“Oh god,” Barry winced. “You broke Batman.”
“I didn’t mean to!”
“You laughed at a toddler!” John scolded, scooping Bruce into his arms and bouncing him gently. “Children are sensitive.”
“I didn’t think Bruce would be!”
“You thought wrong.”
Bruce continued crying, fists to his eyes.
Clark groaned, walked over, and took the kid into his arms. “Alright, alright. Come here.”
He sat on the couch with Bruce in his lap, gently moving his hands away from his eyes. The tears were real, and for a second Clark’s heart just ached.
“I’m sorry,” Clark whispered. “That was mean of me. I shouldn’t have laughed.”
He brushed Bruce’s hair out of his face and gently ran his fingers through the raven strands. Then, instinctively, he began to hum—an old lullaby his mother used to sing on sleepless nights.
Bruce’s sobs began to soften. Then stop.
The little vigilante let out a quiet sigh and curled against Clark’s chest.
“I’m sorry, Bruce,” Clark said again.
“…’kay,” Bruce mumbled.
Barry blinked. “Clark, that was… surprisingly effective.”
Clark smiled faintly. “Mom always said I had a lullaby voice. I used to sing my nieces and nephews to sleep.”
“Sing it again,” Bruce mumbled.
Clark chuckled and ruffled his hair. “Alright, but you better not critique my pitch.”
Barry snorted. “I will.”
Later that night, J’onn returned to the lounge.
“Has anyone seen Bat—”
He paused.
Uno cards scattered. Bruce asleep in Clark’s arms. Barry snoring softly on one side. John dozing on the other. Clark with his head leaned gently against Barry’s shoulder, humming something under his breath.
J’onn’s expression softened.
He quietly dimmed the lights and walked out.
“Sleep well, League,” he whispered. “Bruce is in good hands.”
The morning after…
The Watchtower was unusually quiet the next morning. No alarms. No emergency meetings. No interdimensional incursions. Just the steady hum of space and the peaceful silence of heroes who had finally, somehow, gotten some sleep.
In the medical wing, the bio-scanner gave a soft chime as its readings stabilized.
Then—
A groan.
Bruce Wayne sat up in bed with a sharp breath, hair tousled, expression grim.
He glanced down at himself, noting the absence of tiny limbs, then ran a hand through his hair and muttered, “Back to normal.”
Alfred, who had been dozing in the corner with a cup of tea cooling in hand, looked up. “Master Wayne.”
Bruce blinked. “How long?”
“Roughly fourteen hours,” Alfred said, standing. “You were reverted around midnight.”
Bruce swung his legs over the edge of the bed. “The plant?”
“Destroyed, after thorough analysis. J’onn ensured its pollen will never reach Earth.”
Bruce nodded. “Damage?”
“Minimal. You managed to only punch Mr. Allen once, and not even at full force. Quite restrained, really.”
“…I was three.”
“Indeed. Delightfully so.”
Bruce narrowed his eyes. “What’s that supposed to mean?”
Alfred didn’t answer. He merely offered Bruce a robe and gestured toward the door. “I imagine the others will be pleased to see you up.”
Bruce made his way toward the common lounge, barefoot and scowling as he walked past several League members who very pointedly avoided eye contact.
That was never a good sign.
He entered the lounge.
The sight that greeted him made him stop cold.
Clark was curled on the couch, phone in hand, smiling.
Barry and John were watching something over his shoulder, laughing.
Clark looked up. “Hey.”
Barry turned. “Oh my god, he’s tall again!”
John gave Bruce a once-over. “Welcome back to the land of sarcasm and brooding.”
Bruce crossed his arms. “What the hell happened while I was out?”
Clark smiled, a little too innocently. “Not much. You had a little tantrum. A few emotional outbursts. Bit of training recall. You also declared war on Uno.”
“I did not.”
Clark unlocked his phone, turned it, and showed Bruce the screen.
There it was.
A photo of a tiny Bruce in a Bat onesie (where had they even gotten that?!), arms crossed, glaring up at the camera with the fury of a thousand suns.
Clark swiped.
Another photo.
Mini-Bruce sitting in his lap, curled up, asleep.
Another.
Clark grinning with Bruce perched on his shoulders, arms outstretched like he was flying.
Another.
Barry holding Bruce upside-down while the kid grinned.
Another.
Bruce asleep with his face smooshed into a couch pillow, a Batman plush tucked under one arm, Clark tucked in beside him, humming.
Bruce stared at the phone.
His voice dropped. “Delete. Those. Now.”
Barry laughed. “You really don’t remember?”
“I remember bits.” Bruce scowled. “Training. Diana’s voice. Fighting. Colors.”
Clark smiled. “Yeah, you said that. Then held up ten fingers.”
“…I said four things.”
“You did,” John said dryly. “Math is hard when you’re three.”
Bruce pressed the bridge of his nose.
Clark tilted his head. “I hummed you to sleep, you know.”
“I am aware.”
“And you asked me to sing it again.”
“Fabricated.”
Barry held up his phone. “Nope. Recorded. Want to hear yourself say ‘Ing it ’gain’ in toddler Batman voice?”
Bruce lunged.
Barry yelped and zipped behind the couch. “Kidding! Mostly!”
Clark chuckled and handed Bruce a cup of coffee. “Seriously, though. You okay?”
Bruce took the cup. Sighed. “…As okay as I can be after being transformed into a literal infant and humiliated in front of half the League.”
Clark leaned back, smiling faintly. “You cried when I laughed at your counting.”
Bruce froze mid-sip.
Barry whispered, “He hummed the softest lullaby. It was like an angel gently tapping your trauma into submission.”
“I will break your fingers,” Bruce muttered, sipping the rest of the coffee.
Clark leaned over, elbow on his knee. “You were adorable.”
“I am never adorable.”
“Last night disagrees.”
Bruce gave him a slow, sideways look. “If any of this ends up on League servers…”
Clark raised both hands. “I swear it’s all on private backup.”
Barry added, “I made a folder. It’s called ‘Batbaby Chronicles.’”
“…I’m burning the Watchtower.”
“Worth it,” Barry said with zero regret.
Bruce stood up, robe fluttering like a cape.
“I’m going to the gym,” he said darkly. “Anyone who so much as mentions lullabies will join the punching bag rotation.”
Clark rose too. “Want me to join you?”
Bruce hesitated. His lips twitched.
“…Fine. But you hum again, I drop you through the floor.”
Clark smirked. “Noted.”
As they walked out side by side, Barry turned to John.
“You know, I think this was the best Justice League mission ever.”
John raised a brow. “You mean babysitting the Bat?”
“Exactly.”