Luster Dawn was showing promise in her magical prowess from a young age, so it came as no surprise that she gained her cutie mark in a burst of magic in a similar manner to her mentor (though luckily, unlike Twilight, she didn't break a roof with a giant baby dragon. Only a few loose laser beams and pulses.) Luster Dawn's closest friend at this time was Flurry Heart, so it came natural to her to immediately go visit her and show off her new mark.

Of course, Flurry Heart was amazed, yet... Confused. How could somepony 3 years younger than her get a Cutie Mark first? Twilight Sparkle reassured Flurry that she'd find it soon, and that if she ever needed help, she knew a certain trio of ponies that could help her out.

Beginning of the Side Story, Crystal Mark. It hopefully won't be as long as the main series stories, but it'll be something for everyone to enjoy while I get used to the fact that 2023 is coming up.