If Dipper had his facts straight about traditional Gaelic rituals of mourning-

"Guuuuuuh..."

-and, if he was being honest with himself, he was probably the only person in Gravity Falls who would have those particular facts straight-

"Bluuuuuuh..."

-then his sister was currently... keening.

"Um, Mabel?" He gingerly poked his sister in the shoulder. "Everything okay?"

"Nuuuuuuuh!" Mabel was trembling slightly, staring vacantly ahead at the calendar on the wall of their room. "All my usual happy thoughts are turning up empty, bro. It's like this wacko sad thought showed up and demanded all the lunch money from all the other thoughts, and they're kinda digging through their pockets, and they sorta shrug, like 'Sorry man, I got nothin' today,' and then the sad thought just beats them up anyway."

"Wow. Okay." Dipper frowned. "What was the thought, exactly?"

She just pointed forward, and he noticed that the calendar was open to December. "We're not gonna have Christmas."

"That's not even a little true."

"You know what I mean!" Mabel sighed. "It won't be here. Think about it. What's the best thing in the world?"

Dipper took a moment to picture how his sister's thought process was going. "...Christmas?"

"Of course. But what's the second best thing?" Seeing his blank look, she stamped her foot in frustration. "This town, duh! A Gravity Falls Christmas would blow your mind with how awesomeboss it is! And we're-"

She paused for a second, then glanced back to the calendar. "...And we're not gonna be around," she finished quietly.

He was about to fire back, to argue that it was kind of a silly thing to be upset about. Besides, they'd have their family Christmas, and everyone here would still have Christmas, and no one was really missing out on Christmas, and-

Maybe Christmas wasn't the point.

Something in her expression when she looked down at her feet, and in the slow, bit-by-bit way her smile had faded, told Dipper she was feeling bad about something else. "I'm, uh..." He cleared his throat. "I'm gonna miss them too."

Mabel gave him a quick look, but drooped her head. "Yeah," she mumbled. "I don't like thinking about not being here."

The attic seemed more silent than usual. Dipper played with a frayed edge on his vest, trying to think of something to say, but Mabel's unusual gloominess was making it hard to focus on anything cheerful.

After a moment, he looked back up, determined. "Tell you what. If it's a Gravity Falls Christmas you're looking for, then... geez, I don't know, let's have one."

Blinking, Mabel scrunched up her face with a confused look. "Huh? How the heck are you gonna do that?"

Dipper straightened his cap. "I have a plan," he said confidently. "Um. Sort of."

[]

"Soos, I need your help thinking of a plan."

The Mystery Shack's handyman nodded sagely, setting a bucket of water down. "The words of many a wise man echo in your request, dude. Let's storm some brains."

In the hallway next to the gift shop, Dipper paced back and forth, going over the details in his mind. "What if we could bring in a perfect Christmas-themed thing? Just one big... I don't know, something that would really make this all come together."

"Sounds like you just need a tree, huh?" Soos casually started mopping, unaware that Dipper had spun on his heel and nearly tripped over his own ankles in excitement.

"Yeah, that's perfect!" He grinned, but frowned in concentration just as quickly. "It'd have to be small, though, so we could get it through the doors and stuff. And do you have to look for a certain kind of pine tree, or... oh no, I don't know how to cut trees down! I gotta plan this out."

"Hold up, dude." Swinging the mop up like a guitar, Soos pointed at the entrance to the gift shop. "Feelin' like I should direct your attention to our resident expert lumberjack. Just, you know, seems like it might be a good place to start."

Dipper's eyes lit up. "Wendy! Soos, you're a genius!" Ignoring Soos's bashful 'Oh, stop it,' he raced into the room, past racks of postcards and T-shirts until he nearly collided with the counter.

Behind the cash register, Wendy glanced up from her phone and raised an eyebrow. "Where's the fire, man?"

Dipper threw his hands down on the flat surface. "Mabel's really bummed out because she's not gonna get to see Christmas here so I wanted to help and I want to get a tree to bring back and decorate and everything but I don't know anything about trees or chopping them down so can you help me go find a Christmas tree?"

The torrent of words passed, and Wendy was left with an amused, slightly surprised half-smirk. "In July? Seriously?"

He nodded, no trace of irony or sarcasm in his expression.

"Huh." Wendy looked back to her phone. "Well, you know I only get, like, fifteen minutes for a break. And Stan said make sure to keep an eye on the shop, because you never know when we might get a bus of tourists or something. So, I mean, probably best if I sit this one out."

A little startled, Dipper coughed. "Oh. Well, alright. I guess I just..."

"Dude." She'd already vaulted over the counter, grinning and strolling towards the front door. "I was joking. Let's go chop some trees already!"

[]

Panting, Wendy grabbed a tree branch to pull herself forward. "Dipper, let's go back already."

"What?!" From his vantage point on a ridge a few feet away, he turned back with an incredulous look. "No way! We can't leave until we find the perfect tree, remember? It has to be small enough that we can get it to the attic."

"Well, yeah, but-" A particularly annoying bramble was caught on her belt, and Wendy took a moment to hack it away with her axe. "Couldn't we just cut down a regular tree, then get the top three feet or whatever?"

Dipper scowled. "It's the spirit of the thing! We need to..." His voice trailed off as he stared past the incline in front of him.

"Seriously starting to rethink this, yo," Wendy called from below. She started to make her way up the slope. "Can we keep looking a little closer to the Shack? I'm not even sure where we are right now."

"...No way!" Dipper practically squealed, hands on his head and eyes shining with wonder. "This is so much better! I can't believe it- are you seeing this?"

Grabbing a tree root, Wendy swung herself up the last couple feet. "Gimme a sec- there we go." She stood and dusted herself off, then found herself staring as well. "Is that..."

Dipper grinned. "Mabel's gonna love this."

[]

"Bro, this is stupid."

"Just a few more steps!" Dipper reached back to grab his sister's hand, careful to navigate around the bushes and branches in their way. "I promise, it's gonna be worth it."

"Totally, dude!" Soos was moving through the undergrowth as well, eyes closed. "Although I gotta admit, I'm finding this journey significantly tougher than it would be if I could see. I hope I'm not sounding ungrateful here."

Now standing on the ridge, Wendy smiled. "You're fine, Soos." She helped the others in their climb, then turned her gaze to the sight below here. "All right... Now."

Mabel eagerly opened her eyes.

It was... winter. At first, she didn't even see it as all that strange- simply a frozen forest before her, snow coating the ground as well as the branches of the evergreens all around the clearing. Even red and green twinkling lights drifted down from the sky, adding an otherworldly glow to the scene. With a gasp, she turned her head, but the forest ridge seemed to be the boundary of whatever this was, and regular summer colors graced the trees everywhere except this valley.

"Merry Christmas, Mabel." Dipper was standing next to her, smiling awkwardly, as if he wasn't sure if she would like it. Mabel looked at him for a few seconds, then took a deep breath.

And screamed.

"Thankyou thankyou thankyou this is amazing!" she babbled, tackling him in a hug and rolling down the hill all at once. Before long, they were in the snow itself, and both twins ended up laughing and shivering when Mabel's jump carried them to the bottom of the ravine.

"I didn't really do anything," he mumbled, getting to his feet and still grinning. "We just found it earlier. Some kind of pocket dimension, I guess?"

"Wow!" Mabel didn't really know what the term meant, but everything seemed wonderful and exciting now, so she nodded anyway. "Pocket dimension! That's crazy! Hey, do you think I can hit Wendy from here?" Not waiting for an answer, she scooped up a snowball and threw it back up to the ridge, where Wendy was standing. For her part, the teenager watched the missile fall to the ground a few feet away, then held up her phone to get a better angle for the pictures she was taking. "Aw! She's not playing down here with us!"

Dipper shrugged. "Well, yeah. She helped find this place, though. Far as I'm concerned, she can take as many pictures as she wants."

His sister didn't say anything right away, simply looking between him and the others. Suddenly, she punched him in the shoulder and laughed. "You're the best brother, Dip. This is really cool."

He blushed, but before he could say anything, Soos dashed past, a wide smile on his face. "There's no way I'm not making a snowman, dudes!" He skidded to a stop, looking down at Dipper. "Oh, wait. So, this is where you and Wendy went on that date earlier, right?"

Dipper's expression went blank. "Huh?"

"Dude, you were alone with her for, like, hours. In the woods. That was totally a date, even if you didn't realize it." Soos gave a thumbs-up, then immediately got to work on his snowman.

Falling to a sitting position, Dipper blinked a few times. "Uh..." His mouth was moving, but fully formed words weren't happening. In fact, it sounded a lot like something else. "Uuuuuuh..."

"Uh, Dipper?" Mabel nervously waved her hand in front of his face. "Everything okay?"

"Gruuuuuuh..." Oh, that was it, he remembered. Keening.

Of course, he hadn't really expected a Gravity Falls-summer-Christmas to end any other way.