Thunderdash family!

Characters in order are: Thunderlane, Autumn Wind (Windy), Swift Sprint, and Rainbow Dash

Rainbow resembles her sombra-timeline self because there was a similar war. Less obvious rainbow-power-fication on her because she's already a rainbow, her rainbow power self is really underwhelming compaired to the others, but she does have tinted wing tips (on her one surviving wing).

Rainbow and Thunderlane are both still wonderbolts, it's how they got together in fact, as they had a lot of common ground to discuss during stays at the training grounds and on flights back home to ponyville. They bonded a lot over their shared love of flying, and also both having younger siblings (honorary in the case of RD and Scoots) about the same age too.

Rainbow and Thunder didn't plan to have kids, they didn't even plan to be in a serious relationship, but their fooling around resulted in Rainbow turning up pregnant despite her chances of doing so being low in the first place (I headcanon that 'rainbow' maned ponies have a harder time having kids), but she ended up doing so and decided to keep the kid, ending up with her son Swift Sprint. She was later given a second surprise by getting pregnant with Autumn Wind after getting married to Thunderlane, something she was surprised, exasperated, but happy about all at once.

Swift Sprint takes after his parents, from a young age they coached his flying and he took to it like a fish to water, or a bird to flight in this case. He loves being fast above all things, and takes the greatest pleasure in being able to win a race. He can get competitive sometimes, but overall he has a level head and a fairly chilled out attitude, much like his dad. He isn't as great at fast turns or tricky maneuvers though, and can end up crashing hard, but he's always ready to shake himself off and get back up in the sky.

Autumn Wind is the black sheep, she can fly, and does so very well, being really good at manuvering obstacles and doing figure formations, but she never had the drive for competition that the rest of her family has. Rainbow would often joke that she was meant to be Fluttershys kid instead, in a friendly way that never truly bothered Windy, truth was she did enjoy the slower pace of her 'aunt' Flutters. Her biggest passion is weather maintenace, she loves seeing the seasons change and the effects her work has on Ponyville, what one well placed cloud can do for the plants in the parks and the like. She always competes in The Running of the Leaves festival, going her own pace and enjoying the bright fall colours as the ponies ahead of her shake the leaves off their branches. She'll even take the best leaves home with her, either framing them up as is or turning them into a mural of art.