Twilight recoiled at the question, almost tripping over herself. "W-what? It's been quite a number of years since ponies, as a whole, had anything they'd describe as a 'god', to start." She looked over towards the nearby shelf of books. "I don't remember there being any mention of them in the book I gave you. Where did you get this idea?"
Comforting swayed her tail with thought. "Wrong word," she decided quickly. Harmony had described herself as... "A force of nature, a kind one. What do you call that?"
Twilight inclined her head left and right. "I've never met a force of nature." She suddenly drew a sharp breath. "But you have?! Where? Which one?" A quill and paper appeared beside her, eager to take notes. "How did this happen?!"
Comforting could see she had triggered Twilight, though not in any particularly bad way. "In a dream, but it wasn't very dreamy. Luna visited afterwards." She felt no urge to hide it. The ponies of that world had given her none so far. "She called herself Harmony. Though I'm not sure if she is a she, come to think of it. Do forces of nature have a gender?"
Twilight's quill worked busily as she peered at the little filly that was discussing the gender of something that could be mistaken for a god. "Harmony?" When Comforting nodded, Twilight frowned with fresh thought. "Harmony, and she looked like me?" Comforting bobbed her head all the more. "I... Wait a moment." And she promptly vanished.
Only to reappear. "Right! I don't have that anymore."
"Have what?" Comforting leaned forward, but then it hit her. "Were you looking for your tiara?"
Twilight's eyes widened. "That... yes, I was... But I--" She rolled a hoof, beckoning Comforting to finish the thought.
"You gave it back to the Tree of Harmony." Which is when it clicked for Comforting. "Of Harmony!"
Twilight gently patted the top of the filly. "Exactly what I was thinking. The elements had no sentience, let alone sapience, but the tree is a living creature. It's a tree. An incredibly magical tree. That it could... be sapient is far from impossible, but also isn't something I considered seriously." She was tapping at her chin. "And it appeared to you looking like me?"
"Mostly you." Comforting pointed at her own eyes. "It wasn't that good at pretending to have these, so it just kind of let them stare off into the distance. So, do you know why?"
"I can guess." Twilight sank before her pupil. "I've interacted with it before. I've interacted with you, obviously. If it wanted to approach you in a friendly way, perhaps I was just a good pony it knew that you knew. Still... You haven't done anything... that should have drawn its attention." She leaned in, quill working beside her. "There are a thousand questions I have that only you can answer, but you are a child, and my student. I want to respect your autonomy." A sly smile appeared on her face. "But that doesn't mean I can't ask, just that you can say no. So, may I ask about who you are, Comforting?"
Comforting's ears pinned on her head. "I suppose you have the right to ask." But would she answer? "I don't want to be treated special. I'm just a filly." She worried her hooves together. "I'm having a lot of fun, learning, here."
"And I don't plan to stop you from doing that," hurriedly assured Twilight. "And what you tell me won't be shared if you prefer?"
Comforting tapped at the little student's desk she was sitting in. "I am an 'Old Soul', except more literally than usual." Twilight was leaning in, quill working busily. That she was curious was hard to miss. "I had a whole life already, the whole thing, childhood to... the end." She ran a hoof from the left of her desk to the right in a pretend timeline. "And all the mess in the middle. The whole thing. I don't regret it."
"And yet... Here you are." Twilight considered the very little filly that seemed at the start of a life. "And you seem to know so little about... When are you from?"
Comforting smiled at that question, giggling a little at it. "Good question, but the wrong one. Um... Did you ever go to Equestria High?"
Twilight fell over herself, as if Comforting had just burst into flames the way she scrambled back. "No. No no. You..." Twilight set a hoof against her head. "How can you know about that?! There just isn't a time or place that'd make..." She set her paper down. "No... No... Calm down..." She began the breathing technique given to her by Cadance. "Calm... To answer your question, yes, I have been there. Why do you ask?"
Comforting smiled brightly. "Imagine another mirror, another world. I came from that one." There, the cards were on the table. She shrank though, fear building in a monstrous wave. "Please don't be scared... Or hate me..."
"But... That only raises more questions." She scribbled her thoughts quickly, paper lifting into the air. "Comforting." The filly's ears perked. "Thank you. For trusting me." A thought hit her. "Is it alright if I discuss this with other teachers?"
Comforting deflated at the idea. "I don't want to be treated strangely... Just a filly. Nothing more or less."
But she wasn't! Twilight managed to not blurt that out. "You are still our student, a cherished student we will do our best to educate." Twilight was sitting up proudly. "But only with your permission."
"Um." Comforting wriggled left and right. "That's why I'm here."
"I mean the sharing," burst out Twilight, correcting the misunderstanding. "I'm sorry. You must understand how fascinating this all is."
Comforting smiled, barely, a tense one. "I can imagine. Miss Sparkle, I'd like to go try those horn exercises now. Thank you for telling me about them."
It was a request to flee. One Twilight looked ready to deny for a moment, but the tension in her ebbed away gently. "Of course... Comforting, you are my student first, a filly after that, and..." She trailed off. Comforting was an absurdly interesting thing third, but she hadn't said it. She didn't really have to. "Tell Fluttershy I said hi."
"Okay." Comforting slid to her hooves, her sputtering horn getting the door open almost smoothly. Practice! "Thank you."
And she was gone.
"You know a filly named Comforting?" Luna sipped from a large mug of coffee. "She said you did, and to ask you. I had thought to ignore it, the prattling of a foal, but something about it..."
"Comforting?" Celestia frowned with thought. "I... Wait... That..."
Luna raised a brow at her sister's reaction, watching the older alicorn struggle through thoughts. "She seemed harmless. Was I wrong?"
"No! No... I... Alright..." She took a slow breath. "Luna, you are experienced with dreams." Luna nodded, not even trying to argue that. "I thought I had one, but perhaps I did not. I dreamed of a ghostly shroud, in the place between. Tired and worn. I offered it kindness, and it accepted it eagerly."
Luna inclined her head slowly. "And then?"
"And then, in the way dreams are, I was in Ponyville. Instead of a shroud, a filly stood beside me." She rubbed at the side of her head. "Thinking back on it, a lot of things didn't quite make sense, but dreams can be like that, and it would be far from the first prophetic one I ever had."
Luna nodded softly at that. "Yours are the only dreams I cannot enter. I had thought... perhaps you were guarded?"
"From you?" Celestia reached across the table, patting Luna's shoulder. "I would never, sister dear. But this filly I was speaking of, she had a name. I hadn't given it to her, and it wasn't hers to start, I feel... Comforting. I gave her to Fluttershy. I thought this was a dream."
"It was not a dream," calmly stated Luna. "I saw her. Her dream felt strange to me, but I, when I arrived, could see nothing amiss in it, just a smiling filly. She called me... pure." Luna colored a little at the memory. "Not a word usually given to me."
"But an apt one." Celestia smiled gently at her less social sister. "You visit ponies at their most vulnerable, wanting nothing but to lend a gentle hoof. Guardian of slumber, a job that requires a certain level of, shall we say, purity to do well."
Luna tapped at the table they were seated at. "Returning to the topic at hoof. This filly; the one you delivered in a sleepwalking daze. Are they safe? Should we be concerned? She seemed... harmless at a glance, but so do many dangers."
"Well, if she is troublesome, she is with Fluttershy, who is with Twilight and the others." Celestia sat upright tall and confident. "I'm certain they could handle whatever comes, and Twilight is likely to keep me updated if anything remarkable comes of it. Nothing in that dream makes me especially worried."
"You know your dreams better than I." Luna slurped down her coffee in a great gulping. "I should get back to it, speaking of that. And you should get to bed. Try not to sleepwalk this time, hm?"
"I promise nothing of the sort." Celestia snapped a floating cookie from the air. One last sweet for bed. "See you in the morning light, sister."
"I will watch over you in the moon's glow." They met in a gentle nuzzle, cheek to cheek before they went their separate ways, to work or to slumber.
"I told you." Starlight had an accusing hoof directed at Twilight. "I told you! That wasn't normal. She isn't normal. Why do we even have foals in this school?!"
"You're getting off topic," calmly advised Twilight. "She has followed the rules, gets along with the other students, and is performing adequately in her classes." She brought her hooves together in a quiet clop at her front. "As students go, I have no complaints about her."
"And yet, here you are, talking about her to the school counselor." She pointed at herself. "That's me! She knows about Equestria High?"
"She's... from another world, like that." Twilight shook her head. "But she doesn't want to focus on that, at all. She just wants to be a filly, and learn filly things, and grow up to be a good pony." She smiled awkwardly. "It's all very nice, it just brings so many questions. That's why we're here, talking."
"Because... she's a great student that's also a visitor from another dimension we don't know about?" Twilight nodded at that summary. "You know, you always could send her by." Starlight reached over, her horn making up the difference as she pulled over a bag full of marshmallows. "I've really nailed my hot cocoa recipe!"
Twilight peered at the bag of fluffy sugar. "Is that a recipe you can get wrong?"
"Yes." Starlight's expression was of flat acceptance. "You can mess it up in countless ways. But you can get it so right too. Either way, send her by, let me talk with her. We can learn more about what makes her tick."
"But that isn't the purpose of this school." Twilight waved back over her shoulder at the school as a whole. "She is a student that wants to learn friendship, and seems eager in that. We should focus on that, as teachers."
"Technically." Starlight leaned in with a sly smile. "I may be on the staff, but I'm not a teacher. I'm a counselor. There is a difference."
"Technically," echoed Twilight, copying the tone. "That means I shouldn't even be talking to you about it, since I only mentioned going over this with her teachers, which you are not."
They glared at each other a moment before Starlight turned her hooves upwards. "Alright, alright. I'll only go as fast as you let me, boss mare. Send her to me when you're ready."
"When she's ready," corrected Twilight, slipping to her hooves.