For those concerned: This is an Alternate Universe where Twilight is the older sister of Shining Armor, and is now closer in age to Cadance than the Mane Six :) Cadance now babysat Shining Armor as a foal as well.
Not long after the discovery of the Elements of Harmony, Shining Armor receives a letter inviting him and his friends to the wedding of Princess Mi Amore Cadenza and … his SISTER?! He hasn’t been able to speak with his sister since he moved to Ponyville, so this mystery princess and Twilight couldn’t have possibly fallen in love, gotten engaged, AND planned a wedding since he moved! Why didn’t she tell him?
Nevertheless, he returns to Canterlot for the wedding, only to find his childhood babysitter being very lovey with his sister. But she’s a bit… different. Perhaps it’s just time - she’s a lot calmer now than she was when they were kids. Or…?
Of course, this story would play out very similarly to the original story, but there are some differences that make it distinct - unlike the story from the Sister Swap, where it would play out exactly the same.
Then there is Flurry Heart, the first-born daughter, and heiress to the Crystal Empire. There was some chatter amongst the Crystal Ponies that wondered whether the line would continue through blood or not, but those questions were soon silenced when Princess (legally Empress) Cadance was spotted showing signs of early pregnancy.
Without announcing it to anyone, Twilight and Cadance managed to find a spell that allowed them to conceive! Along comes Flurry Heart (name may change if I so choose), the first natural-born alicorn seen in Equestria for a VERY long time. also, if I’m being entirely honest, this is one of my favorite Flurry Heart redesigns I’ve ever done. I love her so much.