Future universe. "Sister" Princesses Sunset Shimmer and Twilight Sparkle mourned the loss of Equestria's favorite Princesses - The royal natural-born alicorn sisters Celestia and Luna. In an attempt to win them back, they resurrect them - as fillies.
Set after "We Regret to Inform You" :D Pinkie Pie becomes a mother of six children, not including Pound and Pumpkin Pie-'cake'. Pinkie and Cheese then marry and have kids. The Twins now have to deal with sextuplet additions, making a huge family! :)