You Mabel and Dipper were triplets, you three argued over who got their own room in the shack. In the end Dipper got it, making you and Mabel share a room. You and Mabel were laying down in the attic before hearing a knock on the attic door. You got out of bed, opening the door, seeing Dipper standing there holding his pillow. Mabel was sitting up in her bed, rubbing her eyes.

Dipper: "Can we like.. Have a sleepover?.."

It was clear he missed sleeping up in the attic with you two. You nod, letting him in.