Any warnings in case you are unaware: this story features infantilism, which means grown adult/s acting like infants. Jim is the one who is the "infant" in this scenario, and Uhura is his "mommy". Because of this, Jim does and should seem highly out of character, and has no emotional boundaries, and Uhura bathes and diapers him. The scene is purely non-sexual. If this criteria does not meet your expectations, it would be better to leave now than get your hopes up.

Otherwise, enjoy.

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As soon as she crossed the threshold to her quarters, the door swishing closed behind her, Nyota let out a deep sigh and rolled her shoulders to work out the kinks. It had been a long and stressful shift; she'd had to translate and then negotiate with the species they'd encountered during warp. They'd taken the presence of their ship as a declaration of hostile intent and had prepared to fire in response, and she'd had to find out just what they were broadcasting to them to stop a sector-wide war. It'd taken hours and the level of tension on the ship had been high and palpable throughout the entire ordeal. She damn well deserved some rest and relaxation.

"Mommy!"

She let a smile cross her face at the excited voice and walked the full way into the living area, leaning against the wall, crossing her arms and huffing with amusement as she came upon the sight before her. Jim sat on the floor in front of the couch on his quilt, waving his arms and bouncing, absolutely delighted. He was wearing his favorite footie pajamas, the pale pink one with white bunnies all over it, and the grin on his face was big and bright. It looked like he'd been playing with his stuffed lion before she'd come in, if the way it was still clutched in his hand as he waved his arms in greeting was anything to go by.

He smacked his hands on the ground, hitting his quilt and dropping his lion in the process while he giggled at her. "Mommy, mommy!" he exclaimed, and in his excitement he wound up losing his balance from where he was seated and toppled over onto his side. He laid there for a moment not knowing what to do before grunting and rolling onto his tummy and then laying there like that, squirming to try and get back up.

It made Nyota chuckle before she walked over to him and crouched down at his side, resting her hand over the small of his back and rubbing circles into his spine. "What's wrong baby?" she asked, keeping her voice light and pleasant.

Jim moved his head around to look at her with brilliant blue eyes and an equally brilliant grin. "Mommy!" he declared, kicking his legs, and it made Nyota chuckle again.

"Yes, baby, I'm your mommy. Now let's get you cleaned up okay?" She moved her hand down over the swell of his bottom, lightly patting his cheeks and feeling the fullness of the padding that laid over them, and making Jim wriggle in an attempt to escape her touch in the process. It was obvious that he'd wet himself sometime during their shift, no doubt caused by the tension that had been present during the majority of it (due to the very real possibility of getting bombed), and he clearly hadn't changed himself before getting into the scene – just like she'd told him too. He was such a good boy for her. "You must be soaking wet, honey. You need a bath."

Jim lifted his head again with a pout on his lips. "Bu' mommy…"

"Ah, ah, ah," Nyota said, shaking her finger at him. "No buts. You need to be washed up and that's exactly what's gonna happen. Now up you get." And with that, she delivered a solid swat to his bottom, exerting pressure but no sharpness and making Jim squeak and flinch back away from her hand. Nyota stood, bending to take his hands in hers and gradually encouraged him to get to his feet, walking backwards to lead him to the bathroom as Jim toddled after her.

As soon as they were through the door, Nyota stooped down and turned on the warm taps in the tub, and once the water began to fill it at a steady pace, she straightened up and unzipped Jim's pajamas all the way down to his ankle, sliding the pink fabric off his shoulders and arms and then holding his waist to let him step out of them. Once the onesie was removed, Jim was left in just his diaper, which was bulging with fluid from where it was secured around his hips. She leaned forward and blew a raspberry right over Jim's bellybutton as she stretched around to remove the crinkling wet fabric, making Jim jump and squeal, and when she pulled back to look at his reaction with the soiled diaper in hand, Jim's face was open and beaming.

She easily disposed of it before urging him into the bathtub, soothing his light whines when his feet met the warm water and sitting him down, letting him stretch his legs out to get used to the temperature. Once the tub was full and she turned off the taps (and once Jim stopped splashing water on her and giggling when her uniform became soaked as a result), she cupped some water in her hands and poured it over Jim's head to dampen his hair, grabbing the shampoo and massaging it into the curly blond locks and scalp. The soft strokes and the ministrations on his skull made Jim's eyes fall shut as he leaned into her hands and was lulled into a pleasant doze.

He woke back up with a pout and a scrunched nose when she had to rinse the soap out, but when she dumped a substantial amount of bubble bath into the tub and swirled the water to get the bubbles to sprout up, Jim gasped and cooed with wonder as he batted at the resulting mountains of white foam. After giving him his rubber duck and letting him play with it and giggle when it squeaked, she took advantage of his preoccupation to soap up a washcloth and start scrubbing him clean. It took a while, because Jim kept squirming and flinching away when it tickled, especially when she went to wash his armpits and his tummy, but eventually Jim was fresh and squeaky clean.

He didn't want to get out of the bath when it was time to, and he pouted and whined when Nyota drained the tub, but eventually he let her hold his hands and urge him onto the bath mat. He shivered in the cool air leftover from the bath, so Nyota was quick in drying him off, using their fluffiest towel and making sure everywhere was nice and dry, focusing especially on his face and feet. It made Jim scrunch up his nose, and made him giggle and squirm when the soles of his feet were dried, but it got the job done. When she was finished, his skin was flushed pink and his hair stood on end with remaining dampness, and it made Nyota stifle a snort.

She patted the changing station they had set up in the bathroom and said, "Hop up, angel," and Jim took the cue and crawled onto it with ease, settling on his tummy and spreading his legs around her waist. She got out a fresh diaper and the baby powder, but not before giving Jim his pacifier, letting him suckle on it and close his eyes and relax. That was when she started to apply the baby powder, and the soft touches on his sensitive flesh made Jim let out delicate little squirms, mewling and mumbling around his pacifier until Nyota finished powdering his backside and pressed two little kisses to the two pink cheeks, right over the roundest chubbiest parts and making Jim squeal before rolling him over. She lifted up his legs, holding them up with one hand from behind his knees and using the other to powder everywhere she may have missed. After that, she let his legs fall back around her waist and reached up to stroke his cheek, murmuring sweet nothings to him to get him to relax again, and he did so with a snuffle and a sigh. It was easy to place Jim onto a fresh diaper and wrap it up around his hips and between his thighs once he settled down, and she secured it with tape before pressing a kiss to his abdomen where the trail of hair on his belly started, right over the top of the diaper. She felt Jim's muscles jump under her lips and heard him coo before she straightened back up and tapped his hip to get him to sit upright. He was still heavy with lethargy, suckling contentedly on his pacifier and gazing at her with adoring blue eyes, and she smiled at him before urging him off the table and letting him step back into his footie pajamas from where they'd been pooled on the floor.

As soon as the zipper was all the way up to his collar, Nyota took his hand and lead him back out of the bathroom, leaving him to occupy himself with his toys while she went to change into her own pajamas. Her uniform was still damp from Jim splashing her with water, so, as soon as was behind the privacy wall, she removed her boots, stockings, uniform and bra before rummaging about in her closet for drier clothes. Grabbing her flannel pants and a loose tank top and smoothing the wrinkles out with ease, she then padded back out into the living area on bare feet to warm him up some milk, snatching her PADD up from the bedside table as she did so, passing by Jim as she did. He was sleepily playing with his lion, making it dance and fly about as he pleased, and when he yawned around his pacifier with a little mewl and rubbed his eyes she knew it would only be a matter of time until he nodded off. She had to hurry or else he'd fall asleep right on the floor, the poor thing. So she quickly replicated a bottle of milk at just the right temperature before turning back around to face Jim.

"Jim, sweetheart," Nyota called, and the blond looked up as soon as he heard her, blinking slowly and reaching for her with eager hands. A soft smile crossed her lips, and she opened her PADD, flitting through it for a story to read to him, before sitting in her rocking chair and patting her lap to usher Jim over. "Ready for your beddy-bye story?"

Jim lit up at the words 'beddy-bye story', and crawled over to her with tired excitement, wobbling on his hands and knees and dragging his lion with him by its tail. He pulled himself clumsily onto her lap the second he reached her, digging his bony knees and elbows into her thighs in the process and making her wince, but she didn't say anything. Jim's weight occasionally left her legs numb when he sat on her lap, but ever since they'd started their sessions Nyota had been making an attempt to improve her strength, because Jim fell asleep on her every time she held him when she read to him. By this point she was able to pick him up and carry him – unfortunately only for seconds at a time, but it was just enough for Jim to be utterly delighted about it whenever she did.

He settled down in her lap with one of her arms wrapped around his back keeping him upright, leaning half on her side and half on her front, and when she removed his pacifier it made him whine and scrunch his nose, squirming for it back, but she just set it off to the side and brought the full bottle into his line of vision. She figured offering him milk in exchange for the now absent pacifier would be a suitable consolation price, and she was not disappointed; he immediately latched onto the teat that was directly in front of him and suckled, relaxing into her and lifting a hand subconsciously to hover it over the hand she was using to hold up the bottle as his eyes fluttered shut. Holding him up with an arm around him, she looked down at the story on her PADD in her other hand – one of Jim's favorites – and began reading.

Five minutes in, Jim had nodded off and stopped suckling, the milk mostly drained at that point anyway. He'd lowered his head to cushion it against her shoulder, breathing in and out with soft, snuffling snores, and the sight of the blond being utterly content and at ease made her smile. She turned off her PADD and set it to the side with the empty bottle before sliding her other arm under Jim's knees and lifting him up, stumbling slightly under his weight but managing to hold him and herself upright and keep her balance. She carried him beyond the privacy wall into her sleeping area, placing him into the adult-sized crib that stood beside her bed. His face scrunched up as soon as her arms were off him, and he started whimpering, letting out little "ah, ah, ahhh"s that made Nyota's heart melt. She hurried back out and snatched up his lion before returning to his side and settling it into his arms, where he curled around it and rolled onto his side, burying his face into the artificial fur and snuffling as he gradually sunk back to sleep. With a final stroke to his soft blond hair, she pulled his pale blue blankie up around his shoulders and pressed a gentle kiss to his forehead before stretching her back until it popped and letting out a sigh, cracking her neck as she went about her nightly routine. Jim would wake up in a few hours or so for a change and some more milk, so she needed to get as much sleep in as possible before then.

After brushing her teeth, she plugged in Jim's nightlight and dimmed the rest of the quarters' before crawling under her covers and slipping into sleep.