^{Artist's Description:}
So here's my headcannon on Luna's and Celestia's family (after reading the first few entries of 'The Journal of the two Sisters'
(first thing: used the color palette from spyrothefox for Queen Eternita)

King Infinitus and Queen Eternita
They are the rulers of the alicorn land where Celestia and Luna came from. King Infinitus rules over Space (and Matter) and Queen Eternita (in this picture pregnant with Luna) over time and another dimension which our brains can't comprehend.
As Celestia stated in 'The Journal of the two sister', alicorns age differently than ponies. So while they might look young, these two are actually as old as the world (or the universe), because they created it. They were the first two existing creatures ever, (though nobody knows where exactly THEY come from) and the only ones for a long time two. But after a few millenias Queen Eternita brought the twins Prince Exanimes and Anima to live.

Prince Exanimes and Anima
These two are the first children of the King and Quenn of the alicorn land and therefor the older brothers of Luna and Celestia (though they do not know them).
They are the bringers of life (Anima) and death (Exanimes). While Infintus and Eternita created world, Anima filled it with live.
Birds, insects, plants, mushrooms, bacterie, Giffons and also ponies (and the rest of the alicorns actually, though they are not nearly as powerful as the royal family). He's still, to this day, responsible for every given life on earth and also sometimes tempers with his own creation (Evolution).
When Exanimes found out what his responsibility/talent as, he was devastated. He loved the creatures Anima brought forth just as much as Anima himself did an refused to fulfill his duty. But as time passed on, he learned that it was necessary, since if nobody took away the living things Anima created… there soon wouldn't be enough place for everyone. They would start to fight eachtother for land and resources. Which ist why the first ever war started, where Exanimes finally accepted his talent and took a lot of lifes away. In time, he actually found some joy in delivering creatures from the hardship that is live. He takes their 'souls' (which are actually part of Prince Anima's magic) and reunites them all in place only he knows. Maybe it's a place on earth, maybe somewhere else in the universe Maybe it's in his head oder maybe he collects the magic to become stronger than Prince Anima so he can finally overcome his brother and stop him from having him fullfil his dreadful duty (but that are just legends ponies tell eacht other. The last one's from a very evil, but not true, interpretation of Prince Exanimes).
They both don't live among other living things anymore are currently in a more… spirit like status (which is why Celestia, Luna and actually nobody besides their parents know that they exist for sure. There are some legends about them though)

Princess Celestia and Luna
As is stated in the who, Luna is the younger sister of Celestia (about 500 years younger, but in alicorn years… that's like 10 years)
They were chosen by the ponydom to lead them after the events of Hearths Warming Eve, since they were the children of the rules of the alicorn land. Yeah… and the rest we know from the show.

Got some headcannon as to why Discord exists and how his relationship with Celestia and Luna developed. But that's for another time.

I know a lot of bronies see the Mighty Fausticorn as the creator of the world and I liked that idea for a long time too, but… meh. After I read 'The Journal of the two sistes' this popped into my mind. I actually had plans like this years ago, with another design for the Kind and Queen and the two brothers being twin sisters that looked exactly alike, just with different hair styles. Like it better now

Hope you like it two!
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Quenn Eternita's color scheme from spyrothefox

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