Sam Winchester x half sister!reader
Dean Winchester x half sister!reader
Summary: After losing the final family members you've known at 17, you found out that you had two half brothers. Everything was going smoothly - or at least that's what Sam and Dean thought before they found out you're not sleeping.
Notes/warnings: this was a request from @apalanchen/abandonment anxiety, grief, brief mentions of last trauma, sleep deprivation
The lights of the gas station convenience store buzzed overhead as Dean grabbed another energy drink from the cooler, his green eyes scanning the label with practiced efficiency. Three weeks. Three weeks since he and Sam had gotten that call from Child Protective Services, three weeks since they'd learned about the existence of their seventeen-year-old half-sister, and three weeks since their world had been turned completely upside down.
"Dean, you're gonna give yourself a heart attack with all that caffeine," Sam's voice carried from the next aisle over, accompanied by the rustle of snack packages.
"Says the guy who drinks enough coffee to fuel a small aircraft," Dean shot back, but there was no real bite to his words. His mind was elsewhere, focused on you currently sitting in the Impala's backseat, staring out the window with those hauntingly familiar eyes—their father's eyes.
The memory of that first meeting still felt surreal. A sterile office, fluorescent lights casting harsh shadows across the social worker's tired face as she explained the situation. Their father had apparently had a brief relationship seventeen years ago, and when both of your guardians—your mother and grandmother—had died in a car accident, a DNA test had revealed John Winchester as your biological father. With John dead and no other family to speak of, Sam and Dean were your closest living relatives.
Dean's jaw had clenched at the news, not out of anger toward you, but at their father. Another secret, another life John had touched and abandoned. But when they'd first seen you—small, guarded, clutching a worn duffel bag that contained everything you owned—Dean's protective instincts had kicked in immediately. You were family. That was all that mattered.
"You getting anything else?" Sam appeared at his elbow, arms full of granola bars and trail mix, his long hair falling into his eyes as he studied Dean's face with that analytical expression he'd perfected over the years.
"Just thinking," Dean muttered, grabbing a bag of your favorite chips—something he'd noticed during their first grocery run together when you'd lingered in front of them but hadn't asked for anything.
Dean nodded, his throat tightening slightly. "She's been… different lately. Quieter. More tired."
Sam's expression grew concerned, his eyebrows drawing together in that way that made him look older than his years. “I've noticed it too. She barely touched dinner last night, and this morning she looked like she hadn't slept at all.”
They'd both noticed the dark circles under your eyes, the way you'd started jumping at sudden noises, how you'd begun hovering near them constantly as if afraid they might disappear. At first, they'd thought it was the adjustment period nerves—after all, your entire life had been uprooted. But it was getting worse, not better.
Dean paid for their items, his mind racing as they walked back to the Impala. You were exactly where they'd left you, curled up in the backseat with your earbuds in, but Dean could see you watching them in the reflection of the window. Always watching, always alert.
"Hey, kiddo," Dean said softly as he slid into the driver's seat, catching your eyes in the rearview mirror. "We got your chips."
A small smile flickered across your face, but it didnt reach your eyes. "Thanks."
The word was barely above a whisper, and Deans chest tightened. When they'd first brought you home to the bunker, you'd been shy but curious, asking careful questions about their lives, their work, the strange underground fortress they called home. Now you seemed to be withdrawing into yourself more each day.
Sam twisted in the passenger seat to face you, his expression gentle. "How are you feeling? You seemed pretty tired this morning."
You straightened slightly, and Dean caught the way your hands fidgeted with the sleeves of your oversized flannel—one of Sam's old shirts that had somehow migrated to your wardrobe. "I'm fine. Just… adjusting."
The lie was obvious, but neither brother pushed. They'd learned quickly that direct confrontation made you shut down completely. Instead, Dean started the engine, the familiar rumble of the Impala filling the silence.
"We're about an hour out from the bunker," he announced, pulling out of the parking lot. "You hungry? There's that diner you liked about twenty minutes down the road."
In the mirror, he saw you shake your head. "I'm not really hungry."
Sam and Dean exchanged a look. You'd been eating less and less lately, picking at your food and claiming you weren't hungry. It was starting to become a real concern.
The drive passed in relative silence, broken only by the low hum of classic rock from the radio and the occasional comment about the passing scenery. Dean found himself checking the mirror more frequently than necessary, noting the way your eyelids kept drooping only to snap open again whenever you started to doze off.
When they finally pulled into the bunker's garage, you were fully awake again, that hypervigilant expression back on your face. Dean killed the engine and turned to face you properly.
"Y/n, you sure you're okay? You've seemed pretty wiped out lately."
For a moment, something vulnerable flickered across your features—fear, maybe, or longing—but it was gone so quickly Dean almost thought he’d imagined it.
"I'm fine," you repeated, already unbuckling your seatbelt. "Just tired."
You were out of the car before either brother could respond, grabbing your small backpack and heading for the entrance to the bunker. Dean watched you go, noting the slight tremble in your hands as you punched in the door code they’d taught you.
Yes. After you moved in they put a code on the door in addition of the old key.
"She's not fine," Sam said quietly once you were out of earshot.
"No kidding." Dean scrubbed a hand over his face. "But every time we try to talk to her about it, she clams up."
"Maybe we're coming on too strong. She's been through a lot of trauma—losing her mom and grandmother, finding out about us, moving in with two strangers who happen to be her half-brothers. It's a lot to process."
Dean knew Sam was right, but the knowledge didn't make watching you struggle any easier. They made their way inside, finding you already in the kitchen attempting to make a sandwich with shaking hands.
"Here, let me help," Sam offered gently, moving to stand beside you.
You jerked away from him slightly, then seemed to catch yourself. "Sorry, I've got it."
But Dean could see the way you were swaying on your feet, exhaustion evident in every line of your body. Without thinking, he moved to your other side, steadying you with a gentle hand on your shoulder.
"When's the last time you got a full night’s sleep?" he asked directly.
Your whole body went rigid under his touch. "I sleep fine."
"Y/n." Sam's voice was patient but firm. "You look like you haven't slept in days. And don't say you're fine—we can see that you're not."
For a long moment, you stared down at the half-assembled sandwich in your hands, your breathing shallow and quick. Dean could practically see your internal struggle, the war between wanting to trust them and whatever fear was holding you back.
"I just…" you started, then stopped, biting your lower lip hard enough to leave marks. "It's stupid."
"Nothing you're feeling is stupid," Dean said firmly, his hand still resting on your shoulder. "Talk to us."
You were quiet for so long that Dean began to think you wouldn't answer. Then, in a voice so small he had to strain to hear it, you whispered, "What if you change your minds?"
"About what?" Sam asked gently.
"About me. About wanting me here." The words came out in a rush, like you needed to get them out before you lost your nerve. "What if you wake up one day and decide this was a mistake? What if you realize you don't want a kid sister messing up your lives? What if you just… leave?"
Dean felt his heart crack clean in half. The hand on your shoulder tightened protectively as he processed your words, understanding flooding through him like ice water.
"Is that why you haven't been sleeping?" Sam’s voice was thick with emotion. "Because you're afraid we'll leave while you're asleep?"
Your silence was answer enough. Dean could see the tears you were fighting to hold back, the way your whole body was trembling with exhaustion and fear.
"Oh, sweetheart," he breathed, the endearment slipping out before he could stop it. "Y/n, look at me."
Slowly, reluctantly, you raised your eyes to meet his in the reflection of the kitchen window. What he saw there nearly broke him—raw vulnerability, bone-deep fear, and underneath it all, a desperate hope that you were trying so hard to protect.
"We're not going anywhere," he said firmly, turning you gently so you were facing him properly. "Do you hear me? We're not leaving you. Not now, not ever."
"No what-ifs," Sam interrupted, moving to your other side so you were bracketed between them. "Y/n, you're our family. You're our sister. That's not something that changes based on convenience or circumstances."
"But you didn't even know I existed a month ago," you whispered, fresh tears spilling over despite your efforts to contain them. "And your lives were fine without me. You had your routine, your work, each other. You don't need some random kid complicating everything."
Dean felt anger flash through him—not at you, but at every adult who had ever failed you, every situation that had taught you that love was conditional and family was temporary.
"Hey," he said firmly, waiting until you met his eyes again. "First of all, you're not some random kid. You're John Winchester's daughter, which makes you a Winchester. And Winchesters? We stick together. We take care of each other. That's what we do."
"Second," Sam added, his voice gentle but unwavering, "our lives weren't fine without you. They were just… incomplete. We didn't know what we were missing until we found you."
You stared at them both, disbelief and hope warring in your expression. "Really?"
"Really," Dean confirmed. "Y/n I know this is scary. I know you've lost people before, and I know trusting us feels like a huge risk. But I need you to understand something—Sam and I, we've been through hell and back together. Literally. And the one thing that's kept us going through all of it is family. And now you're part of that family."
"The most important part," Sam added softly. "Because you chose to trust us, to give us a chance to be your brothers. And that means everything to us."
The tears were flowing freely now, and Dean could see the exact moment your carefully constructed walls began to crumble. You swayed on your feet, the exhaustion finally overwhelming your adrenaline.
"I'm so tired," you whispered, the confession seeming to cost you everything.
"I know, sweetheart," Dean murmured, pulling you into a careful hug. You stiffened for just a moment before melting against him, your small frame shaking with exhaustion and relief. "When's the last time you actually slept? And I mean really slept, not just dozed off for an hour here and there."
"I don't remember," you admitted against his chest. "Maybe… maybe four days ago? For a couple hours?"
Sam made a pained sound behind you. "Y/n, that's not sustainable. You're going to make yourself sick."
"I tried," you said desperately, pulling back to look between them both. "I wanted to sleep, but every time I started to drift off, I'd panic. What if I woke up and you were gone? What if you left a note saying you’d changed your minds? What if I was alone again?"
Dean's throat felt tight with emotion. He'd been on his own plenty of times, knew the terror of abandonment intimately, but he'd never been seventeen and completely alone in the world. The idea of you lying awake night after night, paralyzed by fear, made him want to punch something.
"Okay," he said decisively. "Here's what we're going to do. You're going to get some sleep—real sleep—and Sam and I are going to stay right here with you until you wake up."
"Yes, we do," Sam interrupted gently. "Y/n, you're exhausted. You can barely stand up. Your body needs rest, and your mind needs to know that we're not going anywhere."
You looked between them uncertainly. "But what about your work? Don't you have a case or something?"
Dean shook his head. "Nothing that can't wait. You're the priority right now."
"No buts," Dean said firmly. "Come on, kiddo. Let's get you to bed."
He kept one arm around your shoulders as they made their way through the bunker to your room—a space they'd tried to make as comfortable and welcoming as possible with soft lighting, warm blankets, and a few personal items they'd helped you pick out during a shopping trip. You moved like you were walking through water, exhaustion weighing down every step.
Sam was already pulling back the covers when they reached your bed, his movements gentle and careful. "Do you need anything? Water? Something more to eat?"
You shook your head, settling on the edge of your bed with a shaky sigh. "Just… you're really going to stay?"
"We're really going to stay," Dean confirmed, pulling the chair from your desk over to sit beside the bed. "I'll be right here. Sam will be here too."
Sam nodded, settling into the small armchair in the corner of your room. "We're not going anywhere, Y/n. I promise."
You crawled under the covers slowly, like you were afraid the movement might break the spell. Once you were settled, you looked up at them both with those familiar green eyes, so much like Dean’s own.
"What if I have nightmares?" you asked quietly.
"Then we'll be here when you wake up," Dean said simply. "We'll remind you that you're safe, that you're not alone, and we'll stay until you can fall back asleep."
For the first time in weeks, you looked like you might actually believe them. Your eyelids were already growing heavy, the simple act of lying down enough to start pulling you under after days of fighting sleep.
"Dean?" you whispered just as he thought you'd drifted off.
"Thank you. For… for staying. For not thinking I'm crazy or needy or—"
"Hey," he interrupted gently. "You're not crazy. You're not needy. You're seventeen years old and you've been through more trauma than most adults could handle. Wanting reassurance that the people who are supposed to take care of you aren't going to abandon you? That’s not crazy. That's human."
You were quiet for a moment, processing his words. "I love you guys," you whispered finally, the admission barely audible. "I know it's probably too soon to say that, and I know we barely know each other, but—"
"We love you too," Sam said softly from his corner. "More than you know."
Dean felt his chest tighten with emotion. "Sam's right. You're stuck with us now, kiddo. Whether you like it or not."
A small smile flickered across your face, the first genuine one he’d seen from you in days. "I like it," you murmured, your eyes finally sliding closed. "I really like it."
Within minutes, your breathing had evened out into the deep, steady rhythm of actual sleep. Dean leaned back in his chair, some of the tension leaving his shoulders as he watched you finally get the rest you so desperately needed.
"She really thought we were going to leave her," Sam said quietly, his voice heavy with disbelief and sadness.
Dean nodded, his eyes never leaving your sleeping form. "Can you blame her? Think about her life—everyone she's ever loved has either died or left. In her mind, we're just the next in line."
"We need to do better," Sam said firmly. "We need to find ways to show her that this is permanent. That she belongs here."
"Yeah," Dean agreed. "We do."
They sat in comfortable silence as the hours passed, taking turns keeping watch over their sleeping sister. Every time you stirred or made a sound, one of them was there instantly, ready to offer comfort if needed. But you slept deeply, your body finally able to rest knowing you weren't alone.
It was nearly dawn when you finally began to stir, your eyes blinking open slowly as you oriented yourself. For just a moment, Dean saw panic flash across your features—the instinctive fear that you'd wake up alone—but then your gaze landed on him, and relief flooded your expression.
"You stayed," you whispered, voice thick with sleep and emotion.
"We stayed," Dean confirmed, reaching out to brush a strand of hair away from your face. "And we'll stay as long as you need us to."
Sam was awake instantly, moving from his chair to sit on the edge of your bed. "How do you feel?"
You considered the question seriously, taking inventory of your body and mind. "Better," you said finally. "Rested. Still scared, but… better."
"The scared part will get easier," Dean promised. "The more time that passes with us staying exactly where we are, the easier it'll get to believe that we're not going anywhere."
You nodded, sitting up slowly and rubbing the sleep from your eyes. "I'm sorry. For keeping you up all night, for being such a mess, for—"
"Stop," Sam interrupted gently. "You have nothing to apologize for. Nothing."
"We're your big brothers," Dean added. "Taking care of you, staying up all night when you need us to, dealing with whatever mess you think you are—that’s literally our job now. And it’s not a burden or an inconvenience. It’s a privilege."
Fresh tears sprang to your eyes, but these were different—tears of relief rather than fear. "I don't know how to do this," you admitted. "I don't know how to be part of a family."
"None of us do," Sam said with a rueful smile. "We're all kind of making it up as we go along. But we'll figure it out together."
Dean stood up, stretching muscles that were stiff from a night in the chair. "How about we start with breakfast? I make a mean pancake, and I think we could all use some comfort food."
Your stomach chose that moment to growl loudly, reminding them all that you'd barely eaten in the past few days. You blushed, but there was a hint of your earlier humor in your expression.
"Pancakes sound amazing," you admitted.
"Good," Dean said, offering you his hand to help you out of bed. "And while I'm cooking, you and Sam can figure out what movie we're watching today. Because we're having a lazy day. No hunting, no research, no leaving the bunker. Just family time."
You took his hand, allowing him to pull you to your feet, and Dean was relieved to see that you seemed steadier than you had in days. The sleep had helped, but more than that, he could see that something fundamental had shifted in your understanding of their relationship.
"Are you sure?" you asked as they made their way to the kitchen. "You don't have people depending on you?"
"Right now, the only person depending on us is you," Sam said firmly. "And you're more important than any case."
You were quiet as Dean started pulling ingredients from the refrigerator, but he could see you processing Sam's words, trying to believe them. It would take time—he knew that. Years of abandonment and loss wouldn't be healed by one conversation and one good night’s sleep. But it was a start.
"Dean?" you said suddenly as he began mixing batter.
"Can I help? With the pancakes?"
The request was simple, but Dean heard the real question underneath it: Can I be part of this? Can I contribute? Do I belong here?
"Of course," he said, making room for you at the counter. "You can be my sous chef."
As you moved to stand beside him, carefully measuring ingredients under his guidance, Dean caught Sam's eye over your head. His younger brother was smiling, the kind of soft, genuine smile that Dean rarely saw anymore. They were all healing, he realized. Your presence wasn't just changing your life—it was changing theirs too.
"You know," Sam said conversationally as they worked, "I was thinking we could redecorate your room if you want. Make it more… permanent."
You looked up from the bowl you were stirring, hope and uncertainty warring in your expression. "Permanent?"
"Well, yeah,"!Dean said casually, as if it was the most obvious thing in the world. "This is your home now. Your room should reflect that."
"We could paint the walls," Sam added. "Get some new furniture, maybe some bookshelves. Make it really yours."
The smile that spread across your face was radiant, transforming your entire appearance. For the first time since they'd met you, you looked like the teenager you were supposed to be—hopeful and excited about the future instead of constantly braced for the next loss.
"I'd like that," you said softly. "I'd really like that."
Dean flipped the first pancake with a flourish, grinning at your delighted laugh. "Then it's settled. Today we eat pancakes and plan your room makeover. Tomorrow we go shopping."
"And tonight?" you asked, a hint of anxiety creeping back into your voice.
"Tonight we prove to you again that we're not going anywhere," Sam said simply. "And tomorrow night, and the night after that, and every night until you don't need the proof anymore."
"And even then," Dean added, "we'll still be here."
You nodded, tears threatening again but held back by sheer determination. "Thank you," you whispered. "For everything. For staying, for caring, for giving me a chance to be part of your family."
"Our family," Dean corrected gently. "You're not joining something we already had—you're helping us create something new. Something better."
As they finished making breakfast together, the kitchen filled with the warm smell of pancakes and the sound of your laughter as Sam told increasingly ridiculous stories about Dean's cooking mishaps over the years, Dean felt something settle in his chest that he hadn't even realized was unsettled.
They were a family now. Not just him and Sam anymore, but the three of them together. It would take time for you to fully believe in the permanence of it, and there would probably be more sleepless nights and difficult conversations ahead. But they had time. They had each other. And for the first time in his life, Dean Winchester felt like he was exactly where he was supposed to be.
