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Mabel Pines was following a mystery, and she was gonna figure it out even if it took her all summer.
Sure, her mystery might not be as… mysterious as her brother with his book, but still! A mystery didn’t need to be that serious to be important, no matter what Dipper thought! Her investigation was just as important as Dipper’s!
Their Grunkle Stan was a weird guy. If Mabel wanted, she was sure she could discover all kinds of secrets to uncover about her great-uncle. But first, she needed to solve this one-- her parents did always say that she had a tendency to get distracted, and she didn’t want to get too busy with other secrets before she solved this one!
You’d think that with how much Grunkle Stan liked attention and money, he would love his birthday. It was the one day a year you can be as greedy as you want, and no one can get upset with you! But for some mysterious reason, he refused to even talk about it-- and Mabel could make anyone talk if she wanted to. One of her teachers once described her as a threat to national security, which she had decided to take as a complement.
Mabel hadn’t even realized that she had no clue when her Grunkle's birthday was until Soos’s birthday came and went. She’s never really even considered the possibility that someone would hate their birthday before. Why would they? It was a day all about you! (Unless you’re a twin. But Dipper was easy to share a birthday with since he knew how excited she got and usually let her have the spotlight.)
But then it turned out Soos had… a pretty good reason for not liking his birthday. But she and Dipper fixed it! Sure they didn’t fix it in exactly the way they had been intending, but they’d still made it better!
That’s all she wanted to do for her Grunkle Stan! Make it better!
Cause, despite how silly Mabel liked to be, she wasn’t stupid. She and Dipper were just as smart as each other, Dipper was just better at being patient! So much smarty-pants stuff took forever, and Mabel was a busy girl! You couldn’t blame her for getting bored.
The point was that Mabel wasn’t as unobservant as people thought. And her family was one of the most important things in the world to her- so if one of them was feeling sad, she was going to notice. And her Grunkle Stan? He was practically the textbook definition of sad. If you looked up 'sad, repressed old man' in the dictionary, you'd see a picture of his face.
To be fair, he wasn’t sad all the time! Stan liked to joke that he was a grumpy old man, but he wasn’t that grumpy at all! But sometimes, when he thought no one else was looking, her great-uncle would just… stop. Just stare down at something and frown, like he had remembered something so unbearably sad that he just couldn't keep going.
Mabel knew whatever was making him that upset, she couldn’t fix it. But she could at least give him more things to be happy about, and a birthday is a perfect opportunity to do that! (And maybe a small, tiny part her hoped she could fix it. She knew she probably couldn't, but she had to at least try.)
So of course, to make her Grunkle Stan happy, she broke into his bedroom.
Honestly, she figured that he would be proud of her for breaking into something! He was always excited when one of them commited a crime without him even prompting them to. Just. You know. He might not be too happy about it being his room that she broke into.
But it was for his own good, and as long as he didn’t find out, he could never be uncomfortable with it! Anything is okay if you’re good enough at lying about it! (Maybe she had been spending too much time around Stan and Wendy? Pshhhh, nahhh, she’s sure it’s fine!)
So after making sure to tell Soos to keep Stan busy, she snuck upstairs. Technically she probably didn't have to sneak yet, but it's about getting into the mindset! The door to his room creaked as it swung open, and she found herself flinching instinctually despite the fact Stan was giving a tour at the moment. As long as she is in and out, and Soos does his Soos thing, he’ll never even have to know that she was there!
Creeping into the dark room, Mabel’s face scrunched in disgust. It was dark and kinda smelly and not a very nice room.
If finding his ID or birth certificate doesn’t work, maybe she should just give his room a makeover? He couldn’t be all sad and weird and quiet with glitter everywhere! That would have to cheer him up! That always worked for her, and it worked a solid ten percent of the time on Dipper!
Where to look, where to look?
Ooo, maybe under the bed! That’s where Dipper likes to hide his diary that he thinks Mabel doesn’t know about.
Oh, okay, nope. Just crumbs, and- is that body hair? Ew ew ew, abort bed!
Mabel sprung back up, narrowing her eyes and rubbing her chin consideringly. Grunkle Stan was a conman, so he had to be good at hiding stuff. She just needed to start thinking like her Grunkle and she would find something with his birthdate on it!
She turned to the dresser, giving it a thoughtful glare, then shrugged. It seemed too obvious to her, but maybe that's what makes it a good hiding place?
Pulling open the first draw revealed a pair of boxing gloves and some brass knuckles. She recognized the brass knuckles from when Stan punched those zombies for her and Dipper. They were so shiny!
Staring down at them, Mabel debated with herself. She needed to be fast, in and out! But on the other hand- she really wanted to try those knuckle dusters for herself and she was prettttty sure those were technically illegal in most states. This might be her only opportunity to try them out!
Giving into temptation, she slipped them on. She giggled as she punched the air, feeling like a fighter from that arcade game Dipper and Wendy liked.
“Having a fun time there, pumpkin?”
Mabel twirled around, letting out a squeak. Stan stood in the doorway, arms crossed over his chest. He was glaring, but the sides of his mouth were twitching up into that smile that meant he found one of them cute but didn’t want to admit it.
“Grunkle Stan! I thought you were giving a tour right now!” Mabel laughed awkwardly, putting her hands behind her back and trying to look as innocent as possible.
“I was until Soos started announcing how lucky I am that no one is doing anything in my room. Here’s a tip kid- never tell Soos to keep something secret. He won’t even tattle on purpose so you can’t even get mad at him.”
Sighing, Mabel face-palmed. She then realized face palming was a bad idea, yelping in surprise and slight pain as the metal collided with her face.
Within the next second, Stan was by her side, moving as fast as he did when had seen those zombies. Not for the first time, Mabel wondered if he could do more than he presented. He always complained about his old man body, but the moment one of them was in danger he moved faster than anyone would expect by looking at him.
“Alright pumpkin, I’m taking these back.” He took her hands, gently sliding the brass knuckles off. “These are not for kids. Not until I teach you how to use them, at least. I’ve got a reputation to uphold here, can’t have one of my niblings run around with knuckle dusters and not know how to use ‘em.”
Mabel smiled weakly up at her grunkle. He sighed at her expression, saying, “Alright kiddo, come on.” He continued holding her hand as he led her over to his bed sitting down with a groan and looking at her expectantly. She hopped up onto the bed, looking down at her lap.
“Now then, what were you doin’ in my room? You tryin’ ta rob your poor old grunkle?”
Shrugging, Mabel kept her gaze firmly downward. Maybe if she just doesn’t say anything he’ll eventually give up asking and she could try again another time?
“Come on, kiddo. We both know I’m stubborn enough to stay here all day. And so’re you, but that’ll mean you’ll miss your sleepover tonight. Do you really wanna tell your friends you can’t hang out 'cause you’re busy hanging out in my gross old man room?”
Mabel’s head shot upward, fixing a pleading look on Grunkle Stan. He cracked a smile at her wide eyes, chuckling and shaking his head. “Nope, that’s not gonna work on me this time. It’s either spending the rest of the day sitting around in here, or ya fess up. What's it gonna be?”
Sighing, Mabel rubbed her hands together as she thought. She could tell by the look in Stan’s eyes that he wasn’t joking, and she really didn’t wanna disappoint Candy and Grenda.
“You have to promise to not get mad.” She shrunk into herself, trying to look as sad as possible.
“Yeah, that’s not happenin’.”
She pouted but gave up on that train of thought. If looking all tiny and pathetic wasn’t working there wasn’t gonna be anything to change his mind, so she might as well get it over with. “So... You know how Soos’s birthday was a few days ago?”
“Uh-huh.” Mabel could tell Stan caught onto where this was going, and he wasn’t happy about it.
“Well… I know he was weird about his birthday, but by the end of it, me and Dipper made it better! And he’s still a little sad about his dad ‘n stuff, but he’s not as upset about it anymore! He even said next year we might be allowed to throw him an actual party! So I just thought… If I figured out when your birthday was…”
“That you’d fix it.” Stan sighed, and Mabel cringed at the sound. “Alright, come here pumpkin.” He put his arm around her shoulder awkwardly, like he wasn’t quite sure if he was doing the right thing. She snuggled in instantly, getting as close as she could without outright climbing on top of him.
“Listen, kid. I know you’re trying to help, ‘nd it means a lot. But there’re some things you just can’t fix.”
“But even if I can’t fix it,” Mabel said, voice muffled from shoving her face into Grunkle Stan’s suit, “I can still help. I can throw you a huge party, it’ll be awesome! You just gotta let me try, I know I can help.”
The arm around her tightened as Stan spoke. “But you don’t gotta help anything. It’s just a birthday, there's no need to get all tangled up about it.”
Her chest tightened at her grunkle's words. She knew he was making sense, that she should just let it go, but she couldn't! This was important, Stan was important, even if he didn't think so! Mabel leaned back, not completely removing herself from her grunkle’s embrace but going far enough to look him in the eyes. “But it's not just a birthday! If I can’t throw you the best party you’ve ever seen, how else am I supposed to help make you happy!?”
“What?” Stan's face went slack in surprise. “Pumpkin, the he- heck are you talking about?”
Face flushing, Mabel looked away. She hadn’t meant to say that much. She just wanted him to understand, but it was coming out all wrong. “Nothing?”
“Nope, you already spilled the beans. You might as well keep going.”
Sighing, Mabel looked back to Grunkle Stan. He didn’t look mad, just confused and a little sad. She was trying to make her grunkle less sad, but it looked like she just wound up making it worse. “I just… I know you’re a lot more sad than you wanna seem, and I know there's probably nothing we can do to fix it. But if I can give you more things to be happy about, then maybe that would help!” She looked away, embarrassed. “It’s stupid.”
Stan sighed again, so quietly she could barely hear it. “These kids,” he mumbled, before using the arm still around her to bring her into a tight hug. Mabel hesitated to return it, a part of her wanting to tear herself away to look him in the eyes. She didn’t want him to lie to her, and she had a much better chance of catching it if she could see him. After a moment, she reluctantly returned the hug. If her grunkle needed a hug and she refused to give it, that would only make him feel worse, and she was starting to think she’d done that enough already.
“Mabel, sweetie…” he trailed off, sounding uncertain. “Okay, look. If I tell you a little about why I don’t like my birthday, will you leave it alone?”
“Really!?” A yes was on her lips, but she quickly reconsidered her approach. “Only if you pinky promise to tell the truth.”
The chuckle Grunkle Stan let out vibrated his chest, a pleasant sound. Mabel wanted to feel relieved by it, take it as a sign the lingering sadness had fled him for now, but she could hear the faint traces of melancholy even in his laughter. “Yeah yeah, alright. I pinky promise everything I say’ll be true. But I might not say much-- can’t let you have all my secrets.”
“Good enough!” Mabel wiggled, trying to escape the hug. Her grunkle held on a second longer, like he didn’t want to let go, but released her soon enough that Mabel wondered if she’d just imagined it. She held up her pinky, a wide smile on her lips. This wasn’t quite as good as finding out his birthday and just throwing him the best, biggest party Gravity Falls had ever seen, but this was a close second!
Stan rolled his eyes, but still locked his pinky with hers. Mabel’s smile grew and she swung their hands back and forth, sealing the promise.
“Alright! Now fuss up, old man!”
“Geez, give me a second, will yeah? You're more bloodthirsty than a shark.”
Mabel vibrated where she sat, impatience practically bleeding out of her pores. She’d gone the entire summer only knowing the bare bones about her grunkle, and now he was offering up information! Of his own free will! (Well, mostly. Is it still out of his free will if it's because she broke into his bedroom? Eh, it’s close enough.)
“Alright. The most I can say is that I don’t like my birthday 'cause… it reminds me of someone I’d rather not havta think about.” He spoke slowly, like he was carefully picking each one of his words.
Face falling, Mabel couldn’t quite manage to hide her disappointment. Stan noticed, poking a singular finger in her face. “Hey, don’t give me that look! I told ya I wasn’t gonna say much!”
“But I thought I’d get more than that!” She gestured widely as she spoke, her long sweater sleeves flapping through the air. “How am I supposed to cook a scheme to fix it with that! At least tell me who it is? Pleaseeee?”
Crossing his arms over his chest, Stan shook his head firmly. “Not happenin’. You can’t fix this one. And I don’t need fixin’.” He softened slightly, looking at her pleading expression. “Kid, you don’t gotta scheme 'n conspire, to make me happy. You and your brother do that more than enough on your own.”
“But-”
“No buts. I don’t wanna talk about this anymore, so you’re gonna drop it.”
Mabel opened her mouth to protest again, then stopped. She studied her grunkle’s face, finding real discomfort in every inch of his expression.
“I just wanted to help…” she mumbled.
“I know, pumpkin.” Stan tousled her hair gently, smiling down at her. “But you don’t gotta worry about your ol’ grunkle, okay? I’m more than happy enough. I mean why wouldn’t I be, I’m me!” He shot her a cheeky grin, winking obnoxiously.
She smiled back weakly, uncertainty filling her. She knew he was lying- she could see it in his grin, how it stretched uncomfortably wide, false. But she could also tell how little he wanted to talk about this, and a part of her knew he was right. Whatever happened with whoever her grunkle wanted to avoid thinking about, she couldn’t fix it. If asking about it just reminded him of them, then maybe this was one thing she should leave alone.
“And who could be sad with great niblings like us, right?”
Stan laughed loudly. Mabel couldn't tell how much of it was real and how much was just to make her feel better. “Right. Now come on, I gotta bunch of tourists I abandoned to keep you outta trouble and I need to get back to suckering them out of their money.”
She nodded, hopping off the bed. Stan stood more slowly, groaning about his joints all the while. Mabel giggled, then giggled louder when he glared at her in mock offense. “Race you!” She cheered, bolting through the door.
“Hey, that ain’t fair. Give a man some warning!”
Laughing, Mabel continued to run down to the gift shop. If she couldn’t properly solve her mystery, at least she could annoy her family into forgetting what was bothering them. That would just have to be good enough- for now, at least.
---
“Shhhh!”
Mabel jabbed Dipper with her elbow, receiving a kick in return. “I wasn’t even talking,” he mumbled.
“SHHHHH!”
“But-”
She rolled her eyes, clapping a hand over her brother’s mouth. If he refused to be quiet, she would make him be quiet. She’s put way too much work into this for Dipper to ruin it now!
Dipper glowered at her, licking her hand. “Ew!” She recoiled in disgust. She shoved her hand toward his face in return, trying to wipe it on his cheek, making his smug smile drop as he focused on ducking away from her.
“Guys!”
They both snapped their heads to Wendy where she was crouched behind the chair. “Be quiet.”
“Sorry,” they both chorused, sheepish. They shuffled away from each other slightly, glaring but unwilling to continue making noise. When a sound came from the kitchen, their mini fight was dropped within an instant.
The back screen door swung open, and the voices of two everyone was waiting on slowly grew louder as they slowly made their way inside and into the living room. “Alright, sure, I’ll give ya that. But Mothman? That ain’t real. You can say you saw it all you want sixer, but that doesn’t mean it happened.”
“We have a gnome infestation in the backyard as we speak. You punched a unicorn in the face with our nephew less than a week ago! Mothman is where you draw the line? How is that any more absurd than anything else in our lives?
“It’s not about bein’ more absurd, it’s about the fact that the Mothman isn’t real -”
“Happy Birthday!”
Mabel popped up from her position behind the couch, shouting as loudly as she could the moment her grunkles walked into the room. From the corner of her eye, she could see Dipper scrambling to stand as quick as she did, but still managed to shout on her cue, as did the rest of them.
To the side of her, Soos pulled the string on a party popper, confetti shooting up into the air and falling down around them.
At the entrance of the room, Grunkle Stan and Grunkle Ford stood, one twin more surprised than the other. Ford watched Stan react carefully, smiling when he saw only cheerful surprise on his face.
Mabel ran forward, slamming into Grunkle Ford with a force that made him stumble back slightly but stay standing. Next to her, she saw Dipper doing the same to Grunkle Stan. Ford bent over, hugging her back just as tightly “Nice job, sweetie,” Ford whispered into her hair.
“Thanks for helping me set up,” she whispered back.
Ford pulled away, winking at her. She grinned back at him widely, mimicking the gesture less subtly, before separating from him completely and running over to Grunkle Stan. She smiled at Dipper as they swapped grunkles, then jumped toward Stan, arms open wide for a hug. He caught her, letting out an, “Oof!” as he did.
“Jesus, are you kids trying to kill me?”
“Happy birthday, Grunkle Stan!”
He laughed, a purely happy sound. “Thanks, pumpkin.” He set her down, pulling away to look at her. “Lemme guess- this was your idea?”
Mabel laughed, nodding. “Yep, just me! I had help from absolutely no one else- I’m a mastermind!”
“Hey!” Dipper protested, almost entirely joking in his offense.
“Welllll, I may have had some help,” she conceded.
Stan chuckled, pressing a kiss to the top of her head. “Thanks, kids.”
She beamed at him, flapping her arms joyfully. Ford appeared next to her, Dipper following after him. Stan stared hard at his brother, saying, “It sure is a mystery how you figured out our birthday, huh?”
Smiling blandly, Ford nodded. “However could they have figured it out.”
Rolling his eyes, Stan scoffed before throwing an arm around Ford in a half hug. It only lasted a moment, but it was enough to make Grunkle Stan turn faintly red and Grunkle Ford lose the tension in his shoulders and breathe a quiet sigh of relief. Mable knew that Ford had been worrying about how his brother would react to the surprise, even though she had told him that Stan would love it. She was looking forward to telling him that she told him so.
“Come on,” Stan pulled away, his voice gruffer than normal as if to make up for the display of affection. “If I gotta do this whole party thing I havta eat at least the kids' weight in cake.”
Grunkle Ford followed after him, but protested, “Leave some for the rest of us, Stanley.”
“Ehhh, we’ll see. Depends on how good the gifts are, maybe I’ll be merciful and leave a few slices for the rest of ya.”
Mabel watched as Grunkle Stan walked right past the cake, going straight to Soos and hugging him just as tightly as he’d hugged her, smiling so wide it made Mabel’s cheeks ache just looking at him. Wendy and Dipper chatted in the corner, hogging the chips, while Grunkle Ford was pulled into a conversation with McGucket. For a moment she did nothing but watch, a joy so light in her chest she felt almost like it’d lift her straight up, then yelled, “You snooze you lose,” and bolted toward the cake. She laughed as Stan shouted, and felt, just a little like maybe she’d managed to help after all.