At the end of season 4 with the defeat of Lord Tirek, Twilight and Discord start to experiment with dating each other. It started with them refusing to acknowledge any growing attachments and Twilight swearing it's only because she wants to know more about chaos magic. But soon enough they became honest with their feelings and they have two children, Star Oasis and Mells(Melliflous)
Having two children a hybrid of a powerful unicorn and a also powerful draconnequus is a incredible stressful thing for a stress-prone Twilight. Although Mells is more energetic in learning how to master her magic, Star is terrified of using any of it, he also has a strained relationship with his father.

Other Headcanons:
• Twilight has some scars from her fight with Tirek, most of which have already disappeared.
• Twilight is blind in one eye
• Twilight is Bisexual while Discord is Demisexual Panromantic /meaning a person who can be romantic with any gender BUT needs to get to know them before any sexual attraction occurs/
• Discord loves cuddling, he's kinda like a boa constrictor while hugging though….
• Discord is fluent in alot of languages, he acts as a translator for Twilight's ancient books and scrolls

Draconnequus Lore Headcanons:
• Immortal spirits of dishonesty and chaos, they are entities that dont have the need to procreate. The birth of a pure blooded draconnequus is synced to the birth of their own personal chaos dimension. Which inherently keeps them away from other Draconnequus and usually other people. Discord was able to escape his own chaos dimension and wreck havoc on other dimensions, before he was stopped during his time at Equestria.
• Draconnequus are able to reproduce with any species; they're Intersex, having both male and female reproductive systems. But the draconnequus has to be the one to give birth to the child since it would be strenous and dangerous for their partner to do so, since hybrid draconnequus come in the shape of an egg. /okay that's it. im not talking about the bird n the bees anymore xD/
• A group of draconnequus is called a pandemonium
• All Draconnequus have weak and sensitive noses.