Hey guys! I have no idea what I've written here. I was inspired to write this story when was remeniscing about being twelve, that rocky age where you're somewhere between teenager and kid and everything starts happening. I just thought it would be a little bit of fun! Don't forget, if you like it, review! And I'm also open for requests for stories, so if you have any ideas (within reason, of course) just give me a message! and no, I haven't forgotton "Return to The Falls", that chapter is in the pipeline. Expect it soon!

And as always, I don't own Gravity Falls.

"Good morning, Mabel!"

The young boy beamed brightly as he rolled over in bed, and brushed his sleep- ruffled chestnut hair out and away from his eyes as he focussed on the wooden slats of the ceiling above him. The warm July sunlight streamed in through the window, illuminating the specks of dust that danced through the air, the sunbeams kissing his cheek lightly as he remembered the wonderful dreams and restful slumber he had awoken from. Dipper Pines breathed in he fresh morning air sharply through his nose as he sat up and stretched, his arms towering high above him as a low groan rumbled from his throat.

"What a morning, sis!" He exclaimed, recounting the fact that he very rarely woke in such a good mood. Yawning and rubbing the sleep from his eyes, he turned toward the bed that was opposite his, expecting his sight to fall on the figure of his sibling, her small body wrapped in blankets as she smiled toothily at him behind excited, yet bleary eyes. However, he soon realised that his sister was absent from her usual spot, a sight that wouldn't usually alarm him too much. What really caused alarm however, was the fact that her blankets were missing, the bears and stuffed animals she usually treasured so reverently scattered in abandon on the wooden floor.

Dipper looked up and around. Well, he reasoned. That's pretty weird, he mumbled to himself as he stood up, his back arching in the sunlight as he yawned, and padded toward the bathroom, his footsteps coming in large slaps on the wooden floor. But as his hand touched the cool metal of the knob of the old door, a shocked voice whimpered from inside.

"DON'T COME IN!"

"Huh?" The boy stepped back in shock. Well, at least he now knew where she was. The sound of running water splashing in a sink reached his ears, causing him to hop a little on one foot. Something wasn't quite right about the sounds coming through the door. Dipper knew his sibling far too well, she very rarely yelled at him from the bathroom like this. Usually, it would be a singsong "Wait a minute!", or she would open the door with a mouthful of toothpaste, her eyes bright and face wet from washing. Dipper leant against the cool wood of the door, feeling the paint crumble a little under the touch of his fingertips. "Mabel… what's wrong?"

No answer. Just the gurgle of the tap inside, and a strange indeterminate whimpering.

"I'm coming in, Mabel," The twelve-year-old took the handle in his hands and turned it with a click, the protests of his sister blaring as the door creaked open.

In the middle of the room stood his counterpart, her long thick hair that usually fell down her back like silk now crumpled from sleep. Her eyes glistened as she stepped away from him, her hands held tightly behind her back, gripping what appeared to be a huge pile of sheets. She was wrapped in a thick bathing robe; a blush filling her cheeks as she averted her face in what Dipper could swear was shame.

"What's wrong, sis?" He stepped tentatively toward his distressed sibling, turning the tap off as he advanced. The girl mumbled in answer, gathering the sheets up even tighter behind her back as she blushed harder. Dipper hated seeing his sister like this; it was unnerving to see her so uncharacteristically upset. But hey, he reasoned. It could be worse. It could be Sweatertown.

"Go away, Dipper," She mumbled in answer, her hazel eyes avoiding his as she gripped the sheets. She mumbled again, this one quieter and less comprehendible.

"What was that?" the young boy leant closer, placing a worried hand on the girl's towelling-clad shoulder.

"I want mom…" She whispered. Aaah. A girl problem, Dipper's nervously concluded. Gulping apprehensively, he breathed in to brace himself. "Mabel, we're twins. You can tell me anything," He pulled her chin so her face was facing his. "Anything," He pressed onwards, kindly but firmly.

Wordlessly, Mabel pushed the bundle of sheets into her brother's hands, her face now an unflattering shade of crimson as she sat on the closed seat of the toilet behind her. "Sorry," She murmured into her chest, hugging herself as she sniffed pathetically. "This has never happened to me before,"

Dipper unravelled the tangle of sheets in his hands, wet in parts from the assault it had inflicted on it from the sink. Dipper held up the sheet in his hands, blinking in slight surprise at the sight before him. In the middle of the cloth was a great scarlet stain, the huge mark stark against the bright white that surrounded it.

Dipper had heard of this event, whispered on rumours to him from the other boys, usually accompanied with giggles and gasps of fascinated disgust. The young boy had joined in with them, and over a game of Nort one evening had quizzed Mabel about it. She had shrugged in disinterest, and promptly destroyed his character, dancing in celebration as she teased him about his terrible gaming skills. The boy heaved a sigh as he gathered the tainted sheet into his arms, silently cursing his sister's terrible timing and wishing there was an older woman somewhere that could help her. However, since their mother was back in California and Wendy was most likely still in bed at her house at this hour, it slowly dawned on Dipper that for now, it was up to him.

"Mabel," He began, breathing heavily. This wasn't going to be easy. "There's nothing wrong with you,"

"I know… it's just embarrassing…" She looked up at him, her eyes shining. "Mom said that a guy shouldn't ever see it! I just woke up and there it was and I freaked out and now you've seen it and you're a guy even though you're my brother and please don't tell Grunkle Stan!" Mabel was standing now, her hands out in front of her as if pleading him. She whimpered as her hands covered her eyes and turned away. "You must think I'm disgusting,"

"Mabel, it's just growing up," He took a seat on the side of the bath, looking up at his sister as he fiddled with a corner of the sheet, watching her begin to pace. He couldn't believe how much this was affecting her.

"It's easy for you to say!" She turned toward him, pointing an accusing finger in his direction. "You guys never get anything happen to you! You just get taller!"

"That's not true!" It was now Dipper's turn to blush as he recounted a few… incidents. "We guys have it pretty bad too!"

This caught Mabel's attention. She faced him, her eyes shining as a tear rolled down her cheek. "Like what?"

Oh crap.

"It's nothing," He croaked, feeling the tips of his ears heat up as it was now his turn to avoid his sibling's gaze.

"That's not fair!" She wailed, pointing to the dreaded bloodstain. Groaning, she flopped onto the floor, pulling her knees up to her chest and buried her head into the soft comforting material of the robe.

"Mabel…"

"Mabel's not here. She's in Robetown," Was the muffled answer, the dome of her head peeking out small strands of chocolate hair as she began to rock herself.

Double Crap. Dipper groaned as he remembered what a great start to the day they had. Now, instead of breakfast, he had been fed a heaping bowl of angst and awkwardness. Dropping to his knees, the boy crawled over to his twin and sat before her.

"You're not doing this to me, Mabel,"

"But I don't want to be a girl," She whimpered as she buried herself deeper. "It's so easy for you guys,"

Dipper rolled his eyes at this comment. "Come out, Mabel,"

"No,"

Dipper was nearly at his wit's end. Breathing in and praying for patience, he realised he knew how to snap his sister out. Unfortunately, it meant bringing them to an even playing field.

"Mabel," He began, gearing himself up as he recounted it. "If I tell you the most embarrassing puberty story I have, will you come out of Robetown?"

An eye peeked out from the slit of fabric, and very gently nodded. "Can't be worse than mine,"

"Ohhh… it can," Dipper groaned, gritting his teeth as he recalled the horror. "It really can. But you must swear on your life that you can't tell anyone or tease me about it. Okay?"

The mass nodded again. The boy breathed in as he prepared himself, and with a long exhale, began his story.

"Do you remember that really hot day last month? And we all went to the lake to swim? Well, you were with Candy and Grenda, and I was hanging around on some rocks around the other side, just soaking up some sun. Anyway, I heard Wendy's voice and I saw her," Dipper blushed bashfully at the mere memory. "She was laughing and she was with her friends, and they were jumping into the water from the jetty. Anyway, Wendy was wearing a bikini and she jumped in, but she lost her top… her friends were laughing and so was she, even though it pretty obvious she was embarrassed," Dipper swallowed as he continued. "I saw everything, Mabel, and I couldn't stop staring, I didn't mean to, honest, and uh… Well… I kind of…."

"What?" Mabel looked out over the hole in her dressing gown, a look of morbid fascination spread across her face. Dipper looked away and brought his knees up to his own chest, avoiding her gaze.

"Got a little… excited, as Grunkle Stan would say. Anyway, obviously I didn't want anyone to notice so I jumped into the water to cool off, only to find Pacifica in the water behind me,"

"NO WAY!" Mabel was now fully out of Robetown, her eyes wide as saucers.

"Yeah way… she laughed. A lot. Called me a pervert and a peeping Tom… I had to bribe her not to tell anyone. I was mucking out her pony's stable every morning for a week,"

Mabel blinked as she read the humiliation on her brother's face, almost feeling the heat radiating in waves from his bright crimson cheeks. A moment of silence weighed heavily on the room, the atmosphere thick enough to slice with a knife. After a minute or two, Mabel broke the hush with a clearing of her throat.

"I...I think I'm going to go wash these sheets now," Coughing to break the tension, she rose to her feet, gathering the sheets up in her arms.

"Yeah…" Dipper stood up alongside her, staring at his feet as though they were the most fascinating things in the world.

"I guess… growing up is difficult on both genders, huh,"

"I guess so…"

Mabel turned the handle to leave, but as she did, the young girl looked over her shoulder, a kind look gracing her features.

"Dipper… thanks for making me feel better," She smiled.

"Can I pee now?" The pre-teen groaned, the pressure in his abdomen making him suddenly realise why he had entered the bathroom in the first place. The young girl left the room with a "snerk", shutting the door behind her with a click.

"Urgh" He groaned into his hand as he inspected his reflection in the mirror, talking aloud to himself as his voice reverberated in the now empty room. "At least my voice hasn't broken recently,"

Ahhh, triple crap.