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The first time Theo wanders off, Buck barely notices.
Which is probably irresponsible, considering Theo is four years old and currently operating at the energy level of a caffeinated raccoon.
But Buck’s exhausted. The 118 was in the middle of their shift, Eddie’s stuck helping Christopher with a school presentation disaster, and Buck had picked Theo up from daycare on the way back to the station because Carla was running late and honestly? Theo loved the firehouse anyway.
So it should’ve been easy. A few hours at the station. Dinner. Cartoons. Then home.
Instead, Theo disappears.
Not gone gone. Just absent enough that Buck suddenly looks up from the kitchen island and realizes he can’t hear him anymore. And silence from Theo is never a good sign.
Buck straightens immediately. “Okay, where’s the tiny menace?”
Chim points vaguely toward the apparatus bay while scrolling his phone. “He was making truck noises like two minutes ago.”
“That narrows it down exactly zero percent.”
Hen smirks into her coffee. Buck heads downstairs, already calling, “Theo?”
“In here!”
Relief loosens Buck’s shoulders instantly. He follows the voice toward the engine bay and finds Theo sitting beside the truck, happily kicking his sneakers. Talking. Buck slows down, not quite sure who he’s talking to. Theo’s tiny face is animated, focused on someone directly beside him. Except nobody’s there.
“Ohhh,” Theo says seriously. “That’s funny.”
A pause, as though he was listening to a response. Then he giggles. Buck glances around the bay automatically. It’s empty. “Theo, buddy?”
Theo looks up brightly. “Dad!”
“Who’re you talking to?”
Theo answers immediately, like the question is obvious. “My Pops.”
Buck leans against the truck with a tired smile. For half a second he assumes Theo means Connor. Except Theo doesn’t call Connor that. Never has. Connor’s just Dad or Daddy depending on the day. “Oh yeah?” Buck says lightly. “What’s Pops saying?”
Theo gasps dramatically. “He said you forgot my juice box in the car.”
Buck freezes up, because he absolutely did forget the juice box in the backseat. “How did you know that?”
Theo shrugs. “Pops told me.”
Buck stares at him for a second before snorting softly. “Okay, spooky child. C’mon. Dinner.”
Theo stands immediately, then pauses. He turns toward the empty space beside him and waves. “Bye, Pops.”
Something strange prickles down Buck’s spine. But, he shakes it off. Kids are weird. Theo, especially, is weird.
-
The second disappearance happens an hour later. Buck’s helping Ravi clean medical equipment while Theo colours at the table nearby. Or, he was colouring nearby. Buck looks over checking in on him. What he finds instead of Theo and his markers, is an empty chair. Buck straightens instantly. “Theo?”
No answer. Again.
Buck drops the equipment immediately. “Theo Riley!”
“In here!”
Buck follows the voice upstairs toward the loft. He finds Theo sitting outside Bobby’s old office. Chimney never felt right using it, opting to do his paperwork at the dining table.
The door is shut and Theo’s tiny back rests against it comfortably, like he’s keeping someone company. Buck’s chest tightens before he can stop it.
It’s been over a year. Months since Bobby died. Months since the station stopped feeling like home and started feeling like something carefully rebuilt around grief. Buck still catches himself looking for him sometimes. Still expects to hear his voice from the office. Still reaches for his phone after hard calls before remembering there’s nobody to answer anymore.
Theo pats the floor beside him. “Dad, sit.”
Buck obeys before he even thinks about it. “What’re you doing up here, buddy?”
Theo smiles at the closed office door. “Talking.”
“To Pops again?”
“Mhm.”
Buck rubs his palm against his thigh slowly. “Okay,” he says carefully. “Can you tell me who Pops is?”
Theo wrinkles his nose like Buck’s being silly. “My Pops.”
“Right, but-”
Before Buck can finish, Theo reaches up to Buck’s hair. “He likes your curls.”
Buck blinks. “What?”
Theo grins. “He said you get grumpy when people touch them too much.”
Buck stares. Because that’s-. Well that’s true. It was something Bobby used to tease him about constantly, since Buck grew his hair out a bit and lost the hair gel. Buck never talked about that around Theo. Actually, Buck’s tried very hard not to talk about Bobby much at all around Theo because every time he does, something inside him cracks open.
Theo tilts his head toward empty air, listening. Then he nods solemnly. “Oh. Okay.”
Buck’s throat tightens. “Okay what?”
Theo looks back at him. “Pops says you still skip breakfast too much.”
From downstairs Chimney yells, “HE’S GOT YOU THERE.” Buck flips off the floor automatically. Theo giggles so hard he falls sideways against Buck’s arm. And despite everything, despite the weirdness curling beneath Buck’s skin, Buck laughs too.
-
By the third time Theo wanders off, the entire station notices.
“He keeps talking to invisible people,” Ravi says nervously.
“He talks to one invisible person,” Hen corrects.
“Neither of those sentences are comforting.” Chimney says.
Buck points aggressively between them. “You are not encouraging this.”
Meanwhile Theo sits happily on the couch eating animal crackers. “Pops says Ravi screams during scary movies.”
Ravi chokes on air. “How-”
Theo gasps. “He says one time you cried.”
Hen immediately loses it. Buck tries not to laugh and fails spectacularly. Ravi points accusingly at him. “You told him!”
“I swear to god I didn’t!” Buck says, raising his hands in defense.
Theo swings his legs cheerfully. “Pops said it was the dinosaur movie.”
Ravi buries his face in his hands while Chim nearly falls off the couch laughing. Buck watches Theo carefully after that. Everything he says, leaving Buck slightly unsettled. Theo acts as though he is talking to someone that is really there. Not imaginary-friend energy. Not make-believe. Real conversations, every time Theo wanders off to talk to “Pops,” he comes back calmer.
That part hits Buck hardest. Ever since the accident on that bridge, Buck has been trying so hard to make sure Theo was happy and safe. Having his parents taken away from him too soon, and now living with Buck, who for the most part, was a stranger to him. Sometimes Buck still wakes up terrified he’s failing him somehow.
But whenever Theo talks to Pops, that fear disappears from his little face.
-
Later that afternoon, Buck finds Theo in the station kitchen standing on a chair. “Theo-”
“I’m helping!”
“You’re stealing marshmallows.”
Theo considers this. “I’m helping me.”
Buck snorts and lifts him onto the counter. Theo immediately curls against him automatically, warm and sticky and sleepy around the edges. Buck brushes powdered sugar off his cheek with his thumb. “You know,” he says quietly, “you never told me what Pops looks like.”
Theo frowns. “Like Pops.”
Buck sighs dramatically. “You are impossible to interrogate.”
Theo grins, then his expression softens suddenly. “He’s sad sometimes.”
Buck frowns slightly. “How come?”
Theo shrugs lightly. “He misses you.”
The words land like a punch directly to Buck’s chest. Before he can respond, the station tones drop. Hen and Chim move immediately. Ravi grabs gear. Buck slides Theo off the counter, thanking whoever was watching as he sees Carla coming up the loft stairs.
“Okay buddy, emergency rules. You stay upstairs with Carla, okay?”
Theo nods and looks toward the apparatus bay, a big smile taking over his face. “Bye, Pops.”
-
The call is awful, a house fire with two injuries and one fatality. By the time Buck gets back to his house hours later, exhaustion sits heavy in his bones. Theo should be asleep, instead Buck hears quiet giggling from the couch. He follows the sound and finds Theo curled beneath Buck’s hoodie, talking softly into empty space beside him. “…and then Buck got all wet,” Theo whispers. Suddenly Theo bursts into laughter. “I KNOW. He’s messy.”
Buck leans against the doorway. “Wow. Betrayed by a ghost.”
Theo lights up instantly. “Dad!”
Buck crosses the room and drops onto the couch beside him. “You’re supposed to be sleeping.”
“I waited. Carla said I could”
Buck brushes hair off Theo’s forehead automatically. “For me?”
Theo nods. Then he glances beside Buck. “No. Both of you.” Buck’s breath catches as the room suddenly feels unbearably still. Theo studies Buck quietly for a second before reaching up to touch his face. “Pops says it wasn’t your fault.”
Buck goes completely motionless. Because there’s only one thing Theo could mean. Bobby. The house fire. He knew that any loss Buck would carry around inside his ribs every second of every day.
Buck’s voice comes out rough. “Theo…”
“He said you gotta stop thinking maybe if you were faster.”
Buck stops breathing. Nobody knows that thought. Buck never said it out loud. Or he did. But only ever to one person. Theo yawns hugely, utterly unaware he’s just shattered Buck open. “He says you did good.”
Buck pulls Theo into his chest so fast the kid squeaks. Emotion crashes through him brutally.
Grief.
Love.
For one impossible second, Buck swears he can almost feel Bobby there. A warm hand on his shoulder. A steady presence at his back.
Proud.
Theo pats Buck’s chest sleepily. “You okay?”
Buck laughs once, broken around the edges. “Yeah, buddy.”
-
Eddie comes over later to find Buck sitting at the kitchen table staring blankly into cold coffee. “That bad?” Eddie asks carefully.
Buck looks up slowly. “I think Bobby’s haunting the firehouse.”
Eddie drops his bag. “Excuse me?”
Buck tells him everything. The wandering. The conversations. The things Theo somehow knows. By the end, Eddie looks deeply unsettled, which is impressive for the resident skeptic.
“That’s… weird.”
“THANK YOU.”
Eddie sits carefully beside him. Buck hesitates and quietly says “He told Theo not to blame myself.”
Eddie’s expression changes instantly. “Oh.”
“Yeah.” Silence settles between them. Theo snores drifting down the hallway.
Finally Eddie says, “Maybe Theo just… needed him.”
Buck looks down the hall, picturing the little boy asleep in bed, a mountain of stuffed animals around him. Connor and Kameron’s son but biologically his. Legally still temporary in ways that terrify Buck every day, but on the road to being permanent.
He wished Bobby got to meet him. To see Buck all grown up. Theo would’ve attached to Bobby fast. Bobby would have read him stories at the station, made pancakes with him, called Theo “Kiddo” with the same endless patience he’d always given Buck.
“I miss him,” Buck admits quietly.
Eddie snorts softly. “Yeah. We know.”
Buck smiles weakly, and glances at the photo of him and Bobby sitting on the cabinet.
-
A week later, Buck finally breaks. Theo disappears again while Buck’s folding laundry in the living room. “Theo?”
“In here!”
Buck follows the voice toward the hallway. Theo stands in the middle, looking at all the photos, smiling at empty space.
“There you are,” Buck says, relief flooding him instantly. “Buddy, you cannot keep wandering off like this.”
“I was talking to Pops.”
“Yeah,” Buck says softly. “I figured.”
Theo beams. And jumps up and down pointing at a photo. Buck looks at the wall and sees which one. The picture is old. A station barbecue from years ago. Bobby is standing beside Buck with one arm around his shoulders. Both of them were laughing.
Theo smiles brightly at the photo, then he turns toward Buck proudly. “Him.”
Everything inside Buck stops.
Because Buck never called Bobby “Pops.” Not around Theo. Not ever. But Buck had thought about it sometimes, late at night.
Quietly.
Secretly.
Bobby was the father Buck accidentally found after a lifetime without one. Theo smiles toward the empty space beside Buck, like someone’s standing there.
“He said you miss him too much,” Theo says softly.
Buck’s eyes burn instantly. “Oh,” he whispers.
Theo walks closer. “He said you don’t gotta be sad forever.”
Buck breaks, tears spill before he can stop them. Theo pulls him down to his level, wrapping his arms around Buck’s neck with complete certainty. Buck holds him fiercely.
Somewhere in the middle of grief and impossible things, Theo’s tiny heartbeat merges with his own. Buck swears he can feel a hand settle briefly against his shoulder.
I love you, kid.