I wanna be real honest i think this next upcoming episode from the leak that shows allura's backstory seems like a Lie she is making up

because it seems very fishy especially her brother who we see caring for her especially when he can't find her it seems very odd since how her brother called her a fool for losing the nova charm when we first hear him in the special

and i think allura is basically lying to sunny and her pals to get what she wants so she can go home and have the nova charm because she needs it because her brother wants it too for unknown reasons that we just don't yet
so Allura is gonna lie to tell the ponies why she acts the way she is and gonna say that the ponies back in Starlight Ridge never help her and treat her like some monster because she wasn't a pony and they saw her as a predator

so then sunny and her pals would like feel bad for her of how she was treated when she was a child and will forgive her what she did and help her go back home by giving her to nova charm and think Allura is all good now since they found out the truth why she was the way she is

only to not know that it was all a lie she made and wasn't the real reason why she ended up her as Allura made it all up to trick them to finally get what she wants

so yeah i think this flashback we will see is all made up by allura to trick them into getting what she wants