Name: Twilight Moonstone
Nickname(s): Junior, Moonstone, Moony
Species/Gender: Unicorn/Female
Mark/Talent: A cut gem with butterfly wings extending from it. Representing her ability to cut gems in such a way as to "write" spell-matrixes into them. Can therefore cast rudimentary spells by channeling her magic through one of her gems, even though her horn is broken.
Personality: Focused, stubborn. Likes to learn, but prefers to study by doing rather than reading, as she find it difficult to read long texts. A huge nerd, especially when it comes to comic books. Loyal, but sometimes forgets to take other peoples feelings into account. Very self confident, almost to a fault.
Important relationships:Twilight Sparkle (Mother) — Like peas in a pod. They spend a lot of time together, either with Twilight teaching Moony, or them working together in developing new, more efficient ways of writing spells into gemstones. As Moonstone grew up, the former became less and less often, and now its almost always doing work together as equals in knowledge.
Rarity (Mother) — They don't share many interests, and have a bit of difficulty finding things to do together. They still love each other, its just that most of their interactions tend to be a bit awkward. Rarity has tried to learn more about the spell-writing of gems, and Moonstone is subscribed to several fashion magazines, but it's still a bit difficult.
Spike (Brother) — Very close, as Spike spent a lot of time babysitting her and introduced her to most of her still prevailing intersts, such as Comics and Ogres and Oubliettes. They still hang out a lot even as adults, and Spike is one of the few people she feels comforable talking about anything with.
History:
After spending years making lists and trying to plan for everything that could possibly happen, Rarity finally had to sit Twilight down and tell her that is was impossible to plan for everything, she even had Twilight do the math of all possibilities. So she finally had to concede that in this case, she was as ready as she was ever gonna be, and cast the spell that would allow her and Rarity to have a child together. Twilight was the one carrying the foal, as Rarity didn't find the idea of being pregnant very appealing.
After months of avoiding the press, Twilight finally gave birth to a filly, who she named Twilight in accordance to her families traditions. Rarity was feeling quite emotional and dramatic, thus making her second name Moonstone. Luna approved greatly of this, and named herself Moony's godmother.
Not all was sunshine and rainbows though. Just a few months after the birth Twilight was visiting the Crystal Empire when both Flurry Heart and Moonstone suddeny dissapeared, a ransom-note left in their place. After weeks they finally found the kidnappers whom were pretty much beat immediatly by two furious alicorn mothers. It was a bit loo late though, as Moony's horn had been broken and Flurry had become emotionally scarred by the experience. Luckily, Moony was too young to remember any of it.
Moonstone grew up very sheltered and rarely left the castle, since her parents were worried for her saftety. She was homeschooled for a while by Twilight, and a lot of her free time were taken up by self-defense lessons by Tempest, who at this point was captain of Twilight's royal guard. She still had quite a lot of friends, as all her honorary aunts made sure to bing their kids over for play-dates regularly.
She got her mark after visting the Crystal Empire again for the first time since that first disastrous trip. At which point she panicked everyone there again, by suddenly dissapearing for a couple of days. Twilight worked herself into such a frenzy, she accidentally took control of the sun when she didn't want the day to end and make it more difficult to search for Moony. Rarity was eventually able to calm her down, and let the night arrive.
As the second day was nearing it's end, everyone was worried over a repeat of the last nigh, when suddenly Moonstone appeared out of a previouslt unknown passageway in the basement of the castle. A bit dusty, very hungry and thirsty, but unharmed. And with a brand-new cutie mark! Turnes out she had sumbled upon a long lost hideout of one of the most notorious theives in Crystal Empire history; a unicorn, that's the only known thing about them. She'd tripped the automatic locking mechanism, and since she didn't have any magic she couldn't find a way out. But among the treasures there was a book about how to write spells into gems; nothing new in theory, but it described much more sophisitcated ways than equestria was aware of. She claims that from the book she was able to figure out how to write a basic "key" (just an "open"-instruction) into one of the gems, and thus got out and gained her cutie mark.
She continues to study how to write spells into gems, and was the one to suggest the design for Zap Apple's head-band controlled prosthetic. She was still a young teen, so she didn't help make the prosthetic itself, but she did help Twilight in finding and preparing appropriate gemstones.
She currenly lives in Manehattan (much to the worry of her parents) where she goes to the Manehattan University of Magic Theory, studying how spells are built and written, how to write spells into gems and the magic around Earth Pony gem-growth. The last one purely theoretical for obvious reasons,
Trivia:Since Twilight Velvet and Twilight Sparkle share the same fist name, I decided to headcanon that it's tradition in their family to name one of their female children Twilight Soomething. Moonstone was chosen because it sounded dramatic, and I imagine that Rarity would chose such a
Her mane is similar to Twilight's because she doesn't really care about her appearence and just want what is most efficient in terms of not being in the way and easy to maintain. Turns out Twilight had already done the research into this to make her own manestyle, so Moonstone just copied her.
Has well over the necessary number of scarves a person should possibly need, all made by Rarity. She mentioned that she wanted one, and Rarity jumped at the opportunity to bond with her. Turned out it was needed though, as she always seems to loose them.
When Zap Apple lost her leg, Moonstone tried to cheer her up by giving her a membership card to the "Lost a limb" support group (who's only members were Moonstone and Tempest, the latter unaware of this fact). Everyone around mentally facehoofed and tried to usher the young teen away for a reprimand, but were suprised when Zap smiled and agreed on the condition that there would be tea and cookies.
One of the first spells she created by herself and wrote into a gem, was a spell that would read out loud any text that was passed under it. Twilight was first a bit annoyed because "it's not just the same thing" and "how can a daughter of mine cheat reading like this?", before realising that Moonstone doesn't have anything against the texts, it's just difficult for her to read. "The words start to jumble together after a while" giving her headaches. Twilght still feels guilty about her first comments on the invention, and has since helped refine it and spread it to other ponies with reading difficulties.