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Jason sighed at the whine Damian let out, taking a deep breath before softening his expression and turning to him. Tim, his bastard little brother, had suddenly dropped Damian off at Jason’s penthouse. The ten-year-old was already regressed, and the way he smiled around his pacifier, looking at Jason like he hung the moon and the stars, was the only reason the older man ever agreed to babysit the kid.
Right now, though, he kinda regretted giving Tim his address, as Damian only whined when he tried to change him. The kid was laid out on a changing mat on the floor, the green diaper bag Tim had brought sitting next to his head.
“Come on, squirt, you gotta work with me here,” Jason mumbled, watching as Damian squirmed and wiggled, little feet kicking back with a whine.
“Okay, can you at least let me change you before you throw a tantrum?” Jason asked, playfully pulling at the small foot hanging in the air as Damian tried to kick him. He rolled his eyes at the baby, reaching over to pull a diaper from the bag, booping the kid’s nose in the process.
He also found a stuffed bat, which he immediately handed to the kid in hopes of settling him down slightly.
Jason started on the kid’s onesie, internally chuckling at the expensive-looking material that Tim had ensured wouldn’t cause Damian some sort of rash. Surprisingly, Tim took Damian’s regression really well. He made sure to order everything, competing with Bruce over who could spend more money on the kid.
Damian’s room was now filled with stuffed animals and all sorts of toys a baby could ever want. Not to mention his clothes—Tim had taken it upon himself to buy the baby all kinds of outfits and accessories, including the many superhero onesies he kept flooding the family group chat with.
When the blue onesie finally came off, Damian’s arms stretched out as if he had been trapped in the fabric. Jason chuckled at that, tapping the boy’s stomach gently.
“Yeah, gotta get you out of that, hm?” At Damian’s happy coo, Jason smirked, tickling the flesh of his stomach. The sound of the baby’s giggles filled the room, making Jason’s heart feel full in a way that made him want to tear it out and give it to the baby lying on the mat.
He then lifted the boy’s hips, taking off the soiled diaper and cooing at the way Damian’s face scrunched up in discomfort as the cold air hit his bum. He slid on a clean diaper, making quick work of the tapes after powdering the baby up. He did not want to deal with a rash.
“There we go, all cleaned up, aren’t you, squirt?” Jason hummed, lifting the kid into his arms. He then grabbed one of his own shirts from the closet, placing it over Damian’s small figure. The shirt swallowed his frame whole, reaching below his knees as he suckled on his thumb, his other hand clutching at his bat.
Jason shook his head fondly before carrying the kid over to the kitchen, easily settling him into the high chair Tim had oh-so-thoughtfully sent over, along with half the baby section of Gotham’s stores. Damian blinked up at him, kicking his feet against the chair as Jason rummaged through the cabinets for something easy. He finally settled on a jar of mashed bananas, rolling his eyes at the ridiculous brand Bruce had stocked up on (and sent everyone in the family boxes of)—organic, imported, probably hand-mashed by monks in the mountains or something.
He twisted off the lid and grabbed a small spoon, scooping up a bit of the puree before holding it out. “Alright, kid, open up.”
Damian eyed the spoon suspiciously, lips pursed around his thumb. Jason sighed. “C’mon, don’t make me do the airplane thing.”
Damian didn’t budge.
Jason narrowed his eyes. “Fine. I’ll do it.” He lifted the spoon, making a low buzzing noise as he wiggled it through the air. “Here comes the Batplane, inbound for landing—”
Before he could even finish, Damian opened his mouth, taking the bite. Jason smirked. “Yeah, that’s what I thought.”
He kept feeding the kid, alternating between exaggerated flying noises and muttered threats about what he’d do if Tim ever dropped Damian off unannounced again. Damian, oblivious, just kicked his feet happily, giggling every time Jason made another sound effect.
By the time the jar was empty, Damian had managed to get some of the food on his cheeks, his nose, and somehow, even in his hair. Jason sighed, grabbing a napkin to wipe him down. “You’re a menace, you know that?”
Damian just giggled, reaching for him with sticky hands.
Jason sighed again—but still let the kid grab onto his shirt.
Feeling a little more awake now, Damian wiggled excitedly in his arms, looking up at him with wide, expectant eyes. Jason raised an eyebrow. “What? You got energy now?”
At Damian’s eager little nod, Jason huffed a laugh. “Alright, alright, but if you puke on me, I’m throwing you back at Tim.”
With that, he shifted his grip and tossed Damian up into the air, catching him with ease. The little boy shrieked in laughter, gripping onto Jason’s shirt as he was lifted again. Jason couldn’t help but grin, bouncing him a little before tossing him up once more, higher this time. Damian’s giggles turned into full-on cackles, kicking his legs happily as Jason caught him with exaggerated dramatics.
“Oh no, a tiny demon is airborne!” Jason announced, spinning Damian around as the kid giggled breathlessly. “He’s coming in for an attack—ahh! He got me!” Jason let Damian grab his face with small hands, pretending to stumble backward.
Damian squealed, delighted, and Jason chuckled, holding him close for a second. He pressed a quick, barely-there kiss to the kid’s temple before tossing him up once more, savoring the way Damian’s laughter filled the room.
For all the chaos, Jason couldn’t really bring himself to be mad at Tim for dropping the kid off.
Not when Damian was smiling at him like that.
Jason had just sat down on the couch, Damian curled up against his chest, thumb in his mouth, when the front door clicked open.
“Aw, look at you, all domestic.”
Jason groaned without even looking up. “No. Get out.”
Tim stood in the doorway, still dressed in an expensive suit from whatever Wayne Enterprises meeting he had come from, smirking like he had just won the lottery. He stepped inside, adjusting his tie as he took in the sight of Jason cradling Damian.
“Guess I don’t have to worry about you saying no next time, huh?” Tim mused, walking over and leaning down slightly. Damian, sleepily blinking up at him, barely reacted beyond making a quiet noise around his thumb. The man just stroked his baby brother’s chubby cheek, giving him a soft smile when he cooed up at him.
Jason scowled. “Next time? Who said there’s gonna be a next time?”
Tim hummed, unconvinced. “Uh-huh. Sure. I’ll just let Bruce know you’re the go-to babysitter now.”
Jason flipped him off.
Tim just grinned. “That’s not a no.”
Jason scowled harder, but Damian shifted against him, and just like that, all his anger melted away.
Tim saw it. And oh, like the little bastard he is, was going to be smug about it for weeks.