Oberon is a product of the efforts of the draconequus conservation project that was brought about a few years after Twilight's school was formed. The species was wiped nearly extinct a few centuries back due to infighting and wars. Now that Discord has been reformed and is one of the very last of his kind, he wanted to bring back the species and hopefully with the help of Equestria's creatures have things go better this time (ala it takes a village). Now Discord himself knows he isn't father material or even particularly good at commitment to the smallest of things but this is something he wants to see before his lifetime is up. He takes the plan first to Fluttershy and Twilight in order to help flesh out the idea and iron out the details before bringing a formal request to Celestia, Luna, and Cadence. They agree to take on the project where Discord (who doesn't need to breed to create offspring but simply a form of essence, a small amount of another creatures magic if available or something as simple as fur or scales) fathers his species to carefully selected parents (guardians and guides to the new age of Draconequus young) and the recipients will care for the magically created children.
The ruling parties and the duchesses of harmony very carefully select those who they feel would be best at taking on the heavy responsibility of reviving a nearly extinct species. Celestia, Luna and Cadence all agree to be personally apart of the efforts as well as most of the Mane 6 (AJ and Rarity refrain, as this comes into play not long after Lady Alice was born and Rarity had a very rough delivery). They go on to bring in candidates that they feel are best suited and would want to help out with the revival, and after a few carefully planned months the project is set into motion.
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