Random thought, but you know how everyone claims to remember when the northern island vanished? Even Bonnie says it at one point, even though this happened long enough ago that Siffrin was a kid and is now an adult.
I wonder if the forgetting happened slowly. The way the King's curse crept across the land.
Mirabelle claims to remember someone who was working in the observatory, but gets distressed when she can't remember them, right? And the dreaming one slowly realizes that their sister is... well.
Maybe the island vanished all at once, but the memories of it were gradually erased? I just think that would be neat. Maybe that's why Siffrin couldn't quite pinpoint why they're missing something for so long, even if they knew it deep down.













