You don’t remember why, or if she was even talking to you, but you remember Lyra once suggesting that Harmony is alive. That the concept adapts as time passes, and in that way, it just knows things. Since the powers of Harmony created the castle, interior and all, it would make sense that it just knows how to lay everything out safely.

Still, it could be an interesting source of conversation.

“I don’t care.” Silver Spoon dully replies as she disappears behind a stack of boxes in a storage room, “I don’t even know why I’m here. I should be getting my beauty rest for my birthday party tomorrow.”

That went about as well as you expected, but maybe a different subject is worth a try?