It was often hard to accurately tell time in the Underground, granted the layers of mountain between those beneath in the caverns and the sky - but Frisk had always had a rather accurate internal clock, and it was currently screaming at them to get back to bed because it was late.
Of course, simply drifting back off to sleep when you've just had your first nightmare in months is rather difficult.
Frisk had awoken in the middle of the night from a dream, the remnants of which clung to them like spiderwebs to a casually brushing hand. They weren't entirely sure what had spurred the nightmare to happen, but that was rather hard to focus on - granted the creeping feeling of hands covering their arms, and legs, and beginning to smother their throat in a vice grip of panic.
They let out a soft wheeze that quickly faded into a keening noise of pure pain and despair, and previously unheard footsteps stopped outside of Frisk's doorway.
Chara had been wandering about the house, looking for a way to rid themself of excess energy in hopes of returning to their light slumber, but upon passing by their younger siblings door and hearing a nearly animalistic noise of suffering and fear, they decided to investigate.
Frisk jumped at the sound of their door squeaking on its hinges, and as much as they wanted to dive under the covers to hide themself from the menacing figure they were sure was approaching, they found themself unable to move from their spot perched atop the thick covers. Static filled their mind as the footsteps grew closer, but it suddenly cleared as a familiar hand moved to rest on their shoulder. They looked up to find the familiar face of their older sibling - Chara. It was a welcome sight in their current state, and the lead feeling in their limbs dissipated almost instantaneously as they scrambled to grab at Chara in a fierce hug - clinging as a baby animal does to its mother.
Chara didn't react, instead simply letting Frisk grab and latch onto them as they slowly maneuvered to sit beside them on the soft bed. A soft look of worry began to cover their face at the younger person's actions, and soon enough they wriggled far enough away from Frisk to move towards the lamp Toriel had placed on their bedside table, waiting for the affirmative nod from Frisk to turn it on. Chara was familiar enough with their sibling's current predicament that they knew they needed to be careful and not overwhelm them - lest they go into a dissociative state.
Once the light was on and the two could clearly see each other in the soft glow from the bulb, Chara began to sign - making sure to keep their movements slow easy to read.
The first question was rather simple, just a quick, "Nightmare?" It was best to start with yes/no questions so that Frisk could build themself up to talking. The question was met with a shaky nod as Frisk curled their knees to their chest, the large sweater they wore crumpling up into a blue and purple heap around their lithe frame.
"Can you talk about it or no?" Another yes or no question, but this one hung in the air for a tad longer - the tension nearly tangible between the siblings as Frisk opened and closed their mouth a few times before giving another nod.
Their voice was creaky and halting from a lack of use as they were careful to think over their words. "I-it was... I was back there. In the bad place." They were quick to clarify, but it wasn't needed. Frisk had told Chara enough snippets of their life in the Upstairs - as the three children called it - that Chara could piece together the hurtful home life they faced, and the reasons for their fall.
Chara simply gave a small nod, thinking for a moment before signing again. "It's ok. Remember our rhythm; 4, 7, 8."
Frisk bit their lip and started to follow the breathing pattern, feeling their heart-rate begin to slow back to a normal pace. They always felt safer with Chara around, as they at least somewhat understood the cruelty of the Upstairs.
After two minutes, Chara seemed satisfied with Frisk's breathing and shifted ever-so-slightly closer, still an arm's length away in case Frisk needed space. "Do you want to sleep more?" Frisk gave a wobbly smile, nodding again a little. They were fairly familiar with this pattern, and it gave them a sense of security to know that them and Chara could comfort each other.
When Frisk had first fallen, the Event had already happened - and though no one had ever properly explained it, they were a rather smart kid and had been able to piece together enough of what happened. Chara began to open up to Frisk after a while and were able to properly tell them what had happened.
Frisk snapped back to reality with Chara waving a hand in front of their face, a soft smirk on their face as their shoulders shook in silent laughter before laying down and patting the mattress beside them. Frisk leaned over them, gently pulling on the string to turn off the lamp before shifting over to face Chara. Although they could no longer see their older sibling, the slight heat that radiated from them was comforting and they fumbled for Chara's hands in the dark, holding them close and flicking their eyes up to the other's barely visible face.
Frisk was able to feel Chara's smile as they shifted closer to the other, moving the grip on their hands so that Chara could trace over Frisk's palms. They soon began to trace the pads of their fingertips in lazy, slow motions over their siblings hands. It wasn't quite fingerspelling, and even with the soft taps included, it wasn't quite Morse code - it was something special that Chara had made to comfort Frisk given the fact they couldn't sing. The motions provided a comforting pressure for Frisk, and it always allowed them to fall asleep.
Sure enough, the small child was soon asleep and gently pulled into Chara's arms, nestling against their green and yellow sweater like a tired cat. Chara was still unable to sleep, but they didn't mind as much when they were able to watch over Frisk as they slept, ensuring that no more nightmares plagued the young child's sleep.