I never thought I would ship these two until I fleshed out Trixie a bit and then I thought there was no better lesbian for her than Sunset XD
 
After Sunset Shimmer’s official return to Equestria from the mirror, Twilight Sparkle felt it was her job to help her friend readjust to equine life. She stayed in the castle in Ponyville, giving her a chance to meet all of Twilight’s friends and bond with Celestia again (and this time, her sister Luna). Having already met Starlight Glimmer during one of her trips through the mirror portal, it wasn’t uncommon for Sunset to spend a good amount of time with her. With both being redeemed villains, Starlight thought there was another pony Sunset might like to meet and connect with: Trixie Lulamoon.
 
While Trixie’s short-lived evil behavior was long gone, it was clear she still struggled with the rushed decisions she made to become a powerful unicorn. The Alicorn Amulet, having been used less than a week at the most by Trixie, had proven to be a cursed item rather than an enchanted one. It wreaked havoc on Trixie’s magic, body, and mind, leaving her with magic withdrawals and residual corruption, making her crave the power it once gave her. Even after she became friends with Starlight, it was clear that what was most effected was her mind, effecting her mood and way of thinking. And having been corrupted by dark magic herself, it was something that Sunset Shimmer could relate to. The two bonded heavily over their darker pasts and their younger selves needs to become as powerful as possible. It was a complete shock to Twilight when Sunset admitted that she found Trixie eccentric but charming, and what better way to rejoin Equestrian society than go on a date? Trixie was almost as surprised as Twilight when Sunset Shimmer actually asked her out, although she played it off and would never admit such a thing.
 
The two went on a few dates, getting along better as a couple than either could have hoped. They were very open with each other, even early in the relationship, and discussed things like marriage and children after the first few months of dating. Both Sunset and Trixie agreed that they weren’t particularly interested in marriage, because what was really the difference between being in a relationship and being married besides a piece of paper? The two were confident in being devoted to each other, so they didn’t really concern themselves with a legal event to signify that. It took them years together for them to be ready to have a foal, since Trixie was a traveling magician and Sunset was now a guidance counselor at The School of Friendship. With Twilight and Starlight’s help, Sunset and Trixie planned for a child, with Trixie more than happy to carry the baby and getting pampered the entire time. The couple had struggled on picking a name for most of Trixie’s pregnancy, and when their little colt was finally born, Trixie decided to smash the top two names together before Sunset could debate it any longer, leaving their baby with one of the longest names they know.