I just found the Gravity Falls section (of course there had to be one, I just never thought to look) and I decided to write a little one-shot just for kicks.
I don't own Gravity Falls.
She lay on her bed, head hanging off the edge facing the room. Mabel had mastered the art of knitting upside-down and this was going to be her next masterpiece. Her knitting needles clicked together in a quick rhythm that was putting Waddles to sleep. This sweater was going to be the most perfect sweater ever. She paused for a moment when she heard footsteps. Too light to be Soos, too natural to be Grunkle Stan, who tried to walk as stealthily as an old man with a limp could, and Wendy would be to lazy to climb the stairs. She quickly threw her knitting under her pillow and carefully placed Waddles on top to guard it, planting a kiss on the pig's head. She snatched a magazine off her nightstand and opened it to a random page just as the door opened.
Dipper was buried in the journal, not even bothering to look up as he ran into various fixtures in the room. He finally completed his treacherous journey by landing on his bed, lying on his stomach and staring at a page in the book. Mabel looked over her magazine at him, thankful that he hadn't been paying attention because of the painful fact that she had opened the magazine upside-down. After a few seconds of unnatural silence, Mabel tossed the magazine aside, and after checking to make sure the unfinished sweater was hidden, she got up and settled down by the side of Dipper's bed.
"Sup, Dipper!" Mabel greeted, resting her chin on the side of her twin's bed, looking up at him expectantly.
"Heh," Dipper mumbled in reply as he pulled his ultraviolet light to scan the page for notes. Mabel looked over his shoulder but quickly became disinterested. She got up and took her sweater out of it's hiding place and picked up Waddles, who had hopped off the pillow and was rolling around on the bed. She looked back at Dipper who hadn't moved.
"Uh, okay Dipper, I'm gonna go do totally not suspicious things now, bye!" Mabel was out the door before Dipper even grunted in response. She trotted down the stairs and ran through the house to the gift shop. She dropped Waddles and left him to run around the store as she climbed up onto the seat behind the cash register. She had just started knitting when Wendy walked in.
"Hey Mabel, what's—"
"No time, must focus," Mabel interrupted the teen and began knitting with record speed.
"Whoa, chill out, Mabel. If you keep up like that, you'll end up hurting yourself or something. Those knitting needles are pretty sharp."
Mabel sighed and put her knitting down. The blue and white yarn balls rolled off the counter.
"Sorry, Wendy. I just really need to finish this sweater by tomorrow. It's really important and if its not done tomorrow, it'll be too late."
Wendy walked over, picking up the fallen yarn as she came and looked at the unfinished sweater. She smiled and looked back up at the knitter.
"This is perfect Mabel. Don't worry, you'll get it done." Wendy set the yarn on the counter and, with a reassuring wave, went off to find Soos and see how many of her chores she could pawn off on the handyman. Mabel waved back and then got back to work.
:.:.:.:.:.:
After working for most of the day and waking up early the next to finish the sweater, Mabel was finally finished. She looked at her masterpiece and grinned widely. It was just as she planned it. She looked over at Dipper, who had fallen asleep late last night with his face pressed in the journal. His alarm clock was about to go off and she knew he would be awake soon enough. She hunted in the closet for a box and a bow that she knew she had in there somewhere, and surfaced with a gray gift box and a bright blue bow. Mabel hurried to her bed, noting that the alarm clock would go off momentarily. She folded the sweater hurriedly and tried to shove it in the box, but it was too late. Dipper had just woken up to smash a button on his clock and he was looking at her curiously through blurred sleep vision.
"Yaaaaawn, morning, Mabel. What are you doing up this early?
"Um, nothing suspicious?" Mabel smiled big at her brother as she pushed the gift box behind her back.
"Mabel, I'm not stupid. What is that?" Dipper closed the journal and set it on the nightstand as he turned his attention to his sister. Mabel sighed and revealed the box to her twin.
"Okay, well since you won't be surprised anyway. Happy Birthday, Dipper!" She smiled and handed him the half closed box, quickly slapping the forgotten blue bow on the top.
"Aw, Mabel, thanks!" Dipper smiled and took the lid off of the box. He pulled out a beautifully made white sweater with blue sleeves and a little blue pine tree sewn on the front.
"Whoa, Mabel! You made this? This is so cool!"
"Yep! Now we can be super twins with matching sweaters! Well, not with sweaters that match, 'cause the blue pine tree is your thing, but, you know… sweaters…" Mabel trailed off, losing her train of thought.
Dipper laughed and pulled his sweater over his head. "It's okay, I get it. We can both wear our favorite sweaters and that can count as super twinning, deal?"
"Of course!" Mabel yanked her puppy playing basketball sweater off of a hanger and tugged it over her head. "Twins!" She squealed, dragging Dipper towards the door by his wrist, towards the birthday "surprise" that Grunkle Stan probably had waiting in the kitchen.
So there it is. Man, I need to learn how to write for Wendy; her lines seemed super awkward. Also, Stan's "surprise" is probably food of some kind; I called it that since his cooking is a bit questionable. Just for the record, you know. Reviews are appreciated, thanks for reading this!