A/N: To fans of "All The World's A Toybox," don't worry - I haven't quit the story, I'm just taking a quick break to force a few excess details out my brain. Suffice to say this'll be short, just a couple of chapters long at the most. Feel free to give your opinions, critiques, criticisms and corrections - especially to the typos that creep in at 1 in the morning. Anyway, on with the show - read, review and above all enjoy!

Disclaimer: Gravity Falls, not mine, keeps slipping through my fingers. 5/12/17 - made some corrections (sorry about the typos).

"Good morning, Dipper Pines. It is now 8:00 AM."

Dipper's eyes fluttered upon. "Uurgh," he yawned. "Good morning, Nurse."

"Your breakfast is ready. Should you require entertainment, episodes of Ghost Harassers and Duck-tective have been made available."

"Perfect. What else is on the schedule for today?"

"Your first exercise period is scheduled for 10:00 AM. Lunch is scheduled for 12:30 PM. Your medical checkup has been scheduled for 2:00 PM. Your second exercise period is-"

"I get the picture – same as yesterday. Now, has there been any news on the birthday party?"

"No data available."

"Should've guessed as much. Thanks very much, Nurse."

Yawning louder than ever, Dipper sat up in bed and surveyed the room around him. He had no idea why he bothered; after three straight days, he knew the isolation cell almost off by heart by now, and besides, it wasn't as if anything could possibly have changed in the last few hours since he'd fallen asleep. By now, he was deeply sick of the colour white: the walls were white, the ceiling was white, the floor tiles were white, the couch was white, the table and chairs were white, the bedsheets were white, the bookshelf was white, even hisclothes were white. If it hadn't been for the TV built into the wall across from the couch and the little library of mystery novels beside it, Dipper might very well have gone blind from sheer boredom. But as welcome as the books and TV were, he'd have felt much better if Mabel had been allowed to brighten the place up a little.

Can't be helped, he thought. Medical isolation, remember? Besides, you'll be out in another few days.

Lurching awkwardly out of bed, he collapsed into a chair, wearily munched his way through his cornflakes, before staggering on through his morning routine. On his way out of the bathroom, he couldn't resist checking his reflection in the mirror, hoping against hope that the mark was gone, but no: there it lay, fresh and livid as ever, an angry red triangle blistered across the nape of his neck.

He knew what it meant; he'd known what it had meant from the moment the doctors had uncovered it, even before Grunkle Ford had been called in to help out: at some point during Weirdmageddon, Bill had branded him with his mark of ownership, and now that Bill was deader than disco, the mark had taken revenge on him. As long as that ugly mass of blistered flesh was still there, he was still sick. Ford agreed and confirmed this diagnosis; for good measure, he'd carefully checked all the other participants of the Zodiac Wheel just in case they'd been marked as well, but no: Stan, Mabel, Soos, Wendy, Pacifica, Robbie, Old Man McGucket, and even Gideon had tested negative for the mark.

What makes me so special, then? Why does this mark want revenge on memore than Grunkle Stan and Ford? After all, they were the ones who killed Bill. Maybe it's something to do with the memory gun and the metal plate – maybe the tinkering with their brains immunized them. Or maybe it's the unicorn hair in the Mystery Shack, and I only got the mark because I was outside too long. Or-

He shook his head. He could uncover this particular mystery once he was out of this cell and onto a proper trail of clues. For now, he was too tired and too sick to think of it, especially now that his head was already starting to throb again – another sign that the sickness was rumbling to life again; for now, all he could do was sit back, relax, and wait for the next round of injections. So, he shambled off to the couch, where he promptly collapsed in front of Ghost Harassers.

About twenty minutes later, however, Nurse paused the program. "Apologies for interrupting, Dipper Pines," the medical computer intoned. "You have a visitor."

Dipper silently punched the air. "Is it Mabel?" he asked hopefully.

"Affirmative. Subject facial scan corresponds with identity file for Mabel Pines; pupil scan confirms negative Invasive Entity presence; brain scan confirms no mental tampering. Awaiting your consent or dissent."

"Let her in, Nurse."

There was a soft clicking from somewhere behind the nearest wall, followed by a muted whirring as the airlock door slid open and shut. "Initiating diagnostics," Nurse announced. The clicking came again, as the computer processed the incoming data. "No harmful agents registered. No compromise in visitor health levels. Patient health levels sufficient to allow physical contact. Visitor may now enter: welcome, Mabel Pines."

A moment later, the wall slid apart to reveal the open airlock, and in stepped Mabel, a supernova of colour in the bland isolation cell. Maybe it was the five days spent trapped in the same boring surroundings, but her clothes seemed a thousand times brighter than usual (if that was possible): even the little rainbow-hued comet on her sweater seemed an impossible haze of colours. Immediately upon seeing him, Mabel launched herself at him with a shriek of joy, enveloping him in the biggest Sincere Sibling Hug since the end of Weirdmageddon.

"You have no idea how good it is to see you, bro-bro," she said, once she was able to speak coherently again.

Dipper grinned, and then winced as Mabel's grip threatened to displace a few of his ribs. "I think I could have some idea," he said wryly. "It's good to see you too, Mabel. How are things going out there?"

"Oh, everything's been pretty quiet; even the Manotaurs are taking a break by the looks of things. Last I looked, the Mayor was asking for donations so the town could buy you a get-well hamper."

"What about Grunkle Stan and Grunkle Ford? What are they up to?

There was a painful note to Mabel's smile now – no surprises there: she'd been hit pretty hard when Stan had lost his memories, and next to Ford, she'd been the most driven to help him remember. "They're doing well," she said at last. "Grunkle Stan's and Soos have gotten the Mystery Shack up and running again, along with a whole new bunch of exhibits ready for the next tourist season… though yeah, Stan's still mad he didn't think of the get-well hamper donation idea first, of course. As for Ford, he's still at work on a cure – making good progress too. He says if all goes well, you'll be out of here in the next two days."

"Really?"

"Ford says it's virtually guaranteed!"

"And what about the party?"

"Ready to go the moment you're out. It's gonna be the biggest birthday party we've had in our entire lives; I think just about everyone in Gravity Falls is invited. You should see the way Pacifica's been getting things ready; I think she cracked just about three nails-"

"Wait a minute, wait a minute," Dipper interjected. "Pacifica's been getting things ready?"

"That's right. She thinks the party could use a bit more glitz and glamour, especially after the scare over this whole isolation chamber business, so she's teamed up with me to help plan out the celebration."

"Pacifica Northwest?"

"Yep."

"As in 'blond, rich, snobbish, miles better than the rest of her family but still proud as heck' – that Pacifica Northwest?"

Mabel snorted with laughter. "I think she has a crush on you, Dipper," she said, gigging impishly. "Ever since Grunkle Ford put a moratorium on visitors from outside the family, it's been nothing but 'how's Dipper?' 'is your brother doing okay?' 'when will he be out?' and my personal favourite 'do you think we'll be married in Paris or Milan?'"

"Mabel…"

"I'm serious, she's already picking out a ring! She said she was going for something that matches your eyes."

"Ha-ha, very funny." An idea struck Dipper, and he voiced it a little quicker than he'd preferred: "How's Wendy doing?"

As expected, Mabel laughed – though not as long as she usually did; was it Dipper's imagination or was the pained expression back on her face, just for a moment? "Speaking of unbelievable crushes," she snickered. "She's doing great – but I think she misses you almost as much as you miss her, believe it or not."

"Really?"

"How did I know that was going to get your attention? In all honesty, you should see the present she's got for you: she's spent the last three days getting it ready."

"Something to look forward to, then. Oh, as long as we're talking about good things, how long can you stay?"

"Oh, since you're on the mend, I can stay for as long as I like. And," Mabel added with a grin, "I hear there's an episode of Duck-tective on the daily schedule!"

"Right after Ghost Harassers."

"Awwwww."

"You said you had all day, Mabel; I think you can afford to wait."

"Alright, alright… but I get first choice of videogames."

"You're on. Now, sit down here and let's get on with the show: we've got a lot of episodes to work around my exercise regimen, and I am not gonna let that spoil my day for a change…"

Several hours later, Mabel finally left the isolation cell, whispering a soft farewell to Dipper over her shoulder as she departed. By that point, her brother was almost asleep, slumped across the couch and barely conscious enough to mutter a "g'bye" in her direction. She'd have liked to wake him up, just so they could have a proper goodbye, but she knew full well by now that Dipper needed his sleep: the treatments took a lot out of him, as did the inevitable response, and the fallout from both – physical and mental – was nothing short of devastating. No, it was better this way: at least this way, they wouldn't have to discuss the party; this way, Mabel didn't have to lie to him all over again.

As the airlock door hissed open, she considered waking Dipper up and telling him everything. For a whole minute, she stood paralysed in the doorway, silently grappling with her conscience. But in the end, she didn't go through with it – couldn't: she'd tried the same thing on over a dozen separate visits, and by now she knew confessions like these were completely pointless. No matter what she said, no matter what Dipper learned, he'd forget every single word of it by next morning – along with everything else that had happened that day.

And so she shambled listlessly into the airlock, hating herself with every single step. She knew it would have been pointless, and that by confessing she'd only be bringing down another night of fruitless heartbreak upon her, but her conscience rarely listened to logic. It gnawed incessantly at her as the airlock cycled through its diagnostic procedures, demanding that she turn back and do the right thing, you coward.

Twice, Mabel succumbed to temptation and went so far as to reach for the "Abort Procedure" button, dead-set on striding back into the isolation cell and telling Dipper everything; but on both occasions, she couldn't go through with it. Inevitability kept dragging her back to reality, just as it had on the last few hundred visits.

Grunkle Ford wasn't waiting for her when she finally emerged into the preparation lab. No surprises there, sadly: now that Mabel had well and truly mastered the procedures of regression and reversion, there wasn't much need for him to supervise anymore. These days, Ford barely left his own laboratory, his time spent endlessly formulating the latest treatment for Dipper, only venturing outside when the time came to pay his respects at the cemetery.

But then, Mabel couldn't criticize: she rarely left the Mystery Shack at all anymore. After all, what was left for her out there? A few weathered gravestones, a forest that no longer tolerated intruders, a town empty except for the few desperate scavengers still clinging to the ruins of Gravity Falls, and beyond that, a world that had long since ceased to move her. Like Ford, she had nothing outside the shack's walls: her family was here, her work was here, her few joys left in life were here… and by all accounts, her destiny was here.

For a moment, she surveyed the lab, eyes drifting aimlessly across the banks of machinery that dominated the room: surveillance monitors, molecular fabricators, stasis chambers, and of course the four quantum regression chambers dominating the room. Once upon a time, there'd been a call for more than one visitor at a time, hence the extra chamber, and for a while, the others had come to visit Dipper just as regularly as Mabel: Mom, Dad, Stan, Ford, Wendy, Soos, Pacifica, and even Gideon had all taken on the guise of their younger selves and spent many happy hours chatting with Dipper. But constant heartbreak, worsened by the knowledge that Dipper would always forget the visits, slowly wore away their resolve: most of them simply couldn't bring themselves to visit again, and those who stayed were beset by other problems; violence, disease, and simple old age whittled away at their numbers, the band of hard-won friends slowly dying off one member at a time.

Now, Mabel and Stanford were all that remained – one of them too old, too sick and too augmented to withstand regression, and the other…

She eyed the massive screen looming over the airlock, which was busily spitting out its usual statistics about the isolation chamber's current occupant. "DAY 15695," the digital readout proclaimed. It seemed such a bland declaration, but it was true: fifteen thousand six hundred and ninety-five days had passed since Dipper had fallen prey to Bill Cipher's dying curse; fifteen thousand six hundred and ninety-five days since he'd been committed to medical isolation; fifteen thousand six hundred and ninety-five days since the curse had started eating away at his memories; fifteen thousand six hundred and ninety-five days since he'd stopped aging.

Fifteen thousand six hundred and fucking ninety-five days.

For Dipper, it would always be day five.

For everyone else, it had been forty-three long, miserable years.

No use putting it off any longer, Mabel: Ford needs your help now. It's time to put aside childish things… again.

Groaning wearily, she undressed, removed her fake braces, bagged up her clothes and put them back in the stasis unit. Then, dressed in a deliberately oversized surgical gown, she strode over to the nearest regression chamber, keyed in the reversion program, and stepped inside. As the machine slowly rumbled to life, Mabel took a moment to examine her twelve-year-old self in the mirrored walls of the chamber: the luxuriant brown hair, the wide, innocent eyes, the button nose and the instinctively cheerful grin (now sans braces, of course). Then she took a deep breath and once again said goodbye to the smaller frame, the clear vision, the perfect hearing, the painless freedom of movement, to everything she could still appreciate about her younger form – everything except the lost opportunities.

And then the light blazed down from above. Mabel let out a scream of agony as the quantum energy permeated her body, accelerating her back to her real age; with a series of sickening pops and cracks of reshaping bone, her body stretched upwards, limbs flailing wildly as they swiftly elongated to their adult length. Her hair shrank to a shoulder-length bob, turning grey and dull as it shortened; her skin withered and wrinkled, scar tissue accumulating across her arms and face as the years piled up; her fingers, already grown to adult size, gnarled and twisted with age, the knuckles swelling as arthritis set in hard. She tried to look away from her reflection as she transformed, but the entire chamber was mirrored, forcing her to watch herself warp and shrivel out of shape.

Thirty seconds later, the light switched off, allowing Mabel to topple to the ground. She rose slowly – but then she always got to her feet pretty slowly these days, always taking just a little longer to recover from the day's ordeals. She recalled how often she and the others had suggested using hologram projectors to disguise themselves around Dipper, if only because they'd be a little less painful to use… but then, what would happen if Dipper were to touch one of the holograms? One hug would have easily blown their cover. These days, she welcomed the regression process: quite apart from the joy of being able to spend time with her brother, it at least gave her a chance to enjoy a perfect bill of health for a chance. And as debilitating as reversion was, it never took too long for the pain to fade: with this in mind, she staggered out of the chamber, retrieved her clothes from one of the stasis lockers, and got dressed.

She was fifty-six years of age now, her careworn features raked with old battlescars, her arms lined with the kind of muscles that only sheer, desperate survivalism could grant. Idly scratching at the old laceration still splitting her left eyebrow in half and wincing as her shirt brushed the long-healed bullet wound in her shoulder, she fastened her boiler suit in place, laced up her boots, and marched slowly but surely down the stairs – back into what was once the Mystery Shack.

Grunkle Ford was waiting for her by the front door, still in the process of fastening the locks. Time hadn't been kind to him, nor had the stress of research and the loss of so many old friends: the death of Grunkle Stan had been the worst blow to the old man yet, especially after the year-long struggle with cancer they'd endured. Less than a week after his brother's funeral, Ford had suffered a heart attack, one so disastrous that they'd had to call in help from Pacifica – the only contact in the outside world they could still rely on: for the next month, he'd remained in the care of a private hospital in Los Angeles, clinging to life while Mabel kept the labs running back in Gravity Falls. Even with the best treatment money could buy, it was a long and problematic road to recovery, especially once most of the doctors said they couldn't allow him to leave if he was just going to keep exerting himself: it simply wasn't possible for him to carry on in his usual way at his age, they said.

Ford, being Ford, retaliated by proving them wrong.

Now, Ford's withered body glittered with cyborg augmentations: his heart, his eyes, his lungs, and much of his digestive tract had all been replaced with ingenious mechanisms of his own design, and his ruined legs were now supported by a clattering set of titanium spider limbs, ferrying him about the Mystery Shack with eerie mechanical grace.

"How's Dipper?" he asked.

"He's fine… just as he always is… and always will be. How was the cemetery?"

"Beautiful. You should see it every now and again, have a chat with Stanley. It'll make you feel better."

Talking with the dead was one of Ford's newest habits. Of course, given that ghosts and zombies were a reality, it wasn't as if they couldn't reply, but Ford had claimed that Stan remained silent. "It's good," he'd once rasped hoarsely between sobs after one particularly emotional visit. "It means he's moved on."

"What about the statue in the woods?" Mabel enquired softly.

Ford's brow furrowed with repressed anger, his cyborg eyes flashing red.

"Magical activity's off the charts," he said quietly. "There's no doubt about it: Bill's alive in there, and while he might not be able to de-petrify his physical body, he's definitely up to something – and that something's almost certainly to do with Dipper."