Twin On The Other Side || Gravity Falls AU

Discovery

Mabel yawned, looking around her room. 'Was it morning?' She pondered, she moved her sight to her alarm clock, a weird looking pink cat with a clock on its head, she got it on holiday once. It was 2:12AM, it was morning but not a time she would be up. She looked at Dipper, he slept soundly with a book over his face.
"Must have read himself to sleep again..." she scoffed quietly, she thought again and decided she'll get a cup of water for the time being, she was thirsty anyways. Mabel swung her legs to the side of her bed, rubbing her eyes before proceeding. Once satisfied, she continued her journey, carefully making her way out the room, attempting to make as minimal noise as possible. The young girl carefully shut the door, not to wake her slumbering brother. She was about to go down the hall when the house shook, blue protruded through the cracks in the floor boards. She held onto the doorknob for support, though being weirded out her continued. Making her way down the stairs was a piece of cake, she had memorised all the stairs that squeaked, for you know, for going outside at midnight to have dance parties with Ricky and that random goat, which she named Gompers. As she met the bottom the house shook again, stronger this time, she held onto the banister for dear life, before forwarding on her quest. She had finally made it to the sink, she clambered the counter to reach the cabinet with the cups in.
"Why does Grunkle Ford keeps his cups so high? Maybe he's scared of the miniature cup burglars?" Mabel pondered once again, jumping back down. She began to fill up the pristine glass cup, it was peaceful and quiet till the house shook again, greater than ever before.
"Alright this is getting weird, maybe I should tell Dipper? Yeah, tell Dipper. He always watches films and reads books where this happens, he'll know what to do. Good ol', reliable ol', Dipper." Mabel rambled on, leaving her half-full glass to the side as she went to get her brother. She aggressively shook the young boy upon entering, Dipper slowly opened his eyes.
"What Mabel? It's 2AM!" Dipper babbled drowsily, Mabel took a deep breath.
"Basically I woke up, couldn't go back to sleep, got thirsty, went to get a drink of water. Now this is the part I came to tell you about, at random times the house would just shake and between the cracks in the floorboards, you know them, it was blue!" She attempted to explain, Dipper tilted his head. It happened again, the shaking sent Dipper flying out of his bed. Suddenly, they heard a crash, it came from downstairs. Dipper set off, grabbing his sister by the wrist. They arrived in Ford's experiment room, they were jars of brains and different life forms everywhere, the twins redirected there sight to the floor. There was a fallen metal door on the floor.
"It must have flew off it's hinges..." Dipper guessed, slowly edging closer to the door frame, Mabel squeezing his hand tightly. The house shook again, sending the children flying down the creaking wooden stairs that was hidden behind the door way.

They landed on a hard metal floor, behind and large box. They peeked sneakily from atop the cardboard cube, there was Stanford. He breathed heavily as the portal admitted blue strikes of lightning.
"Yes... Yes... This may be the day..." The elder murmured to himself, continuing to fiddle with machinery. He excitedly ran to a leave, which was placed in the centre of this mysterious room, and gave it a good pull. Without warning, the room collapsed, Ford ducked and covered his head. The young boy and girl squeezed their eyes shut, afraid of what could be upon that gateway.

Brains and the Brawn, that's what they say but a simple mistake made these boys as stubborn as clay.