The baby cries, heartbreaking wails coming through the monitor on the bedside table, the noise-level lights flashing red in the darkness of their bedroom. Kate groans, rolling over into the softness of her pillow, hoping that the baby will just go back to sleep and let them rest but the cries peak once more.
Castle hasn't moved since his head hit the bed and, as she slips from under the sheets, she finds herself surprised that the father at her side hadn't beaten her to the rescue. Still, she snags her robe from the foot of the bed and shrugs it on during the walk into the office.
"What's wrong, baby?" she whispers, leaning over the crib and tracing a finger over the scrunched-up face of the boy. His mouth puckers in surprise, watering eyes blinking up at Kate for just a moment before the cries start again.
Kate lifts the newborn into her arms, carefully adjusting the little body into the crook of her elbow and gently swaying on her feet. The sobs falter, lulling into silence as she walks in slow circles around Castle's desk. "Just lonely without your mother," Kate murmurs, keeping her voice low to calm the baby and avoid waking the man still face-planted on the bed in the next room. "I understand, Cos-" She stops in front of the windows, New York glittering in the night outside. "No. I'm not calling you Cosmo. Not a good name for a baby."
She moves toward the kitchen, pulling one of the bottles of formula from the fridge and sticking it in the warmer Castle bought during his shopping trip spree. The timer starts ticking back from three minutes and Kate shifts her weight from side to side until the bottle is at the right temperature.
"Anyway," she continues, crossing back to the office and settling on the worn suede couch, "I understand the loneliness that comes when your mother isn't nearby. You see, my mother is gone and sometimes I just wish I could talk to her, ask her whether I'm doing things right."
The boy whimpers until Kate teases his lips with the nipple of the bottle, a tiny grunt of happiness escaping the tiny body at the taste of the formula. It makes her smile as she drags the chenille blanket from the back of the couch toward her until it drapes over her shoulders, creating a warm cocoon around her and the baby.
"I'm not a baby person, you know," she says as the boy eats. "It's not that I don't like you guys. I just don't get the appeal." His tiny fingers flick over the plastic bottle as she stares up at her. "I think I'm starting to get it, though. You're pretty cute and all."
He gurgles, looking surprised at the noise and staring up at her with wide eyes until Kate reminds him of the bottle and he goes back to sucking gently.
"Castle went all out for you," Kate muses, taking in the portable crib set up in the corner of the office, the baby bag stuffed with diapers and wipes and burp cloths, the shopping bags overflowing with onesies. "A little overboard but he's like that. Just sort of does what he wants and you know what, baby?" she whispers, leaning close so the blanket falls further over the both of them, a secret darkness around them. "Despite all of that overwhelming enthusiasm, I love him."
But the baby's asleep, little mouth puckered and eyes closed once again.
Kate gets up, slow and careful not to wake him as she walks to the crib. The blanket keeps sliding from her shoulders as she tries to lay him back down, brushing a hand over his so soft hair as he settles into a deeper sleep on the mattress of the bed.
She puts the empty bottle in the sink, her elbows resting on the countertop as she rubs at her eyes in the dim light from the laundry room that spills into the kitchen.
"You love me?"
It draws a quiet laugh from her as she turns to find him standing in the living room, rumpled and sleepy with ruffled hair.
Kate wanders over, stepping right into his arms and burrowing her face down into his chest until he pulls the chenille fabric around the two of them. "Yeah. Definitely love the father of my child."
"You know Cosmo isn't our baby, right?" he asks, pulling back to look down at her.
She nods, nuzzling her nose into the warmth of his neck. "Oh, I'm aware." She tilts back, raising a brow at him and gets to see his face when he figures it out.
"Wait, are you…? Kate," he gasps, pressing a breathless kiss to her mouth. "Oh my god, Kate."
"Good thing you bought all those blankets," she murmurs, tugging him toward their room. "We'll need them in about seven months."
Based on a prompt from the Castlefanfics Prompt Challenge: Season 6 - Blanket.