Just experimenting with Twilight's and Sunburst's kids. I changed Solstice's sex here, I dunno, I kinda like it. I don't have enough female NGs anyways…

Ideas:

-I always felt like Interstellar is the bad, but understandable guy. That's why he looks so grim in his first Bio. But I'm not sure how to handle it yet. Here you can see him as a teenager, very keen on impressing his mommy. He has the best grades and always thinks about his duties. He's not the funniest guy and he certainly knows how to manipulate certain things so that it always ends well for him. I can also imagine Interstellar always kinda liking boys, especially in his teens, but he denied it a lot and maybe spat out a homophobic rant or two. He looks like a christian boy here, doesn't he? Haha. Yeah he probably tried to be very faithful when he was younger.
BUT he becomes a very different adult. More about that later.

-Solstice is a completely different page in the book. She LOVES extreme sports. I can see it in her eyes, the will to risk her life for the sake of adrenaline. She's also very positive would never manipulate anyone. She does love her brother though, and wants to help him when he struggles with his actions or the way he sometimes feels (like Solstice is more loved by people than him). That's why Interstellar feels connected to Princess Luna, and has had a crush on her in his teens (one of his few woman crushes).

Just bits and pieces of characteristics, because I'm still exploring.