Time for one of the royal sisters to have their family shown off, And why not with the unappreciated one of the 2 sisters with her dumb husband.  
*NOTE: This gen was designed before Season 9 and I haven’t watched the final so this is completely headcanon, Also in my universe Celestia and Luna dont retire and instead pass the crown to their children
 
DISCORD
 
After the defeat of Cozy Glow, Discord decided to come help out and fix the school back up for unknown reasons causing both of the princesses to be suspicious of his motives. Celestia invited Discord for a dinner to both give him a sorry for keeping him stoned for 1000 years but also to question him about why he was not there to help out when Cozy manipulated the school. Discord didnt know what was happening and originally planning a gift for Fluttershy. Celestia gave him the go ahead and they both did enjoy their time together, even if Discord does like to annoy the princess. They both made it a thing to do these every week, they unexpectedly started developing feeling for each other.
 
CELESTIA
 
Celestia didnt expect to even gain feelings for the draconequus, She confessed first and Discord hesitated on saying his even having to make jokes while doing it. They had a slow relationship and they kept it hidden for a while until they felt like they could move on to the next step. After they felt like what they were feeling for one another was right, they made it public with a royal wedding. It wasnt exactly perfect and it was more chaotic than elegant but neither of them minded it, Celestia adored her husband who was very confused on love feelings and when they had their twins. Discord didnt know how to handle a foal but with Celestia by his side, he was able to learn hoe to take care of them.
 
DISASTER
 
Disaster is the first twin of Celestia and Discord, He is crowned the new prince and ruler of Equestria. He is more of a chaos bringer as his magic is more related to Chaos instead of Pony magic. He uses his magic for good and of course pranks. He has a hard time being mature and often acts immature and not serious, he is also pretty lazy and doesnt enjoy doing his Prince related tasks and wants to explore Ponyville and be near the normal ponies. While originally the ponies would always bow to him and keep him out of doing simple things, Now they just bro-hoof (fist?) him and let him do dumb things. He isnt seen as a prince to his fellow ponies and more of a friendly commoner.
 
HARMONY
 
Harmony is the second twin of Celestia and Discord, Harmony rejected the offer of begin crowned prince as he felt more happy living his life doing his passion of painting and sculpting. He is very timid as he feels wrong about being a half-pony, he was bullied for being a freak and has felt the guilt of being a half-pony ever since. He has a pony disguise that he prefers to keep and use all the time, While his family tries to make him feel good about himself, he always prefers to keep his disguise up. He has way more normal pony magic than chaos magic like his brother. His brother when not busy will have tea and talk about whats going on, they are stuck to each other like glue and adore one another. Disaster is very protected of his twin brother.