I may have already said it earlier in this thread or at least certainly in others. It is a bit of a shame we never officially got how Starlight got her mark (Not even in the IDW comics when other villains, former or otherwise, had their backstory covered). It turned out to be a blessing in disguise for me as I enjoyed putting my own spin (Though how IDOTS Starlight is not how I’d guess it happened in canon for some obvious reasons) on it. But as I’ve mentioned before, it’s part of how I’ve come to realize Starlight feels like so much missed opportunity. However, at least I’m appreciating her more then I did before. Also as I’ve said before, I feel healthy discussion Starlight provides some oppurtunity to help G4 discussions continue even as G5 goes on, quite possibly with little-to-no references to Starlight.
Spoilery note:The Equestria Girls movies were not canon to I Dream of Twilight Sparkle, and in context Sunset is much older then the Sunset we know. She and Twilight’s mom were fillies at around the same time in this universe. Thought it’d be important to try to reduce the objections to Sunset being not just Starlight’s mother but deceased (having died pretty young.) that I’ve gotten a few times in comments on some of my work here and there from those who didn’t get the full context