SOLVED. Fantasy story about brother and sister being exiled [s]

[Emrick]

I remember reading these fantasy stories (I believe they were a trilogy) in middle school ( around 2007). Random plot points from my very foggy memory:
-The sister wakes up in some musical horn machine after sleeping in it
-The villagers of the town get angry and kick her and her brother out (I think)
-They go into the sewer and there are people living there
-All of the sewer people chew some kind of plant that only grows there
-The siblings make it out and I think there are airships at some point?
-There is some creepy army that act all in sync and never stop smiling
That is pretty much all that I remember, besides that the brother and sister were really close. I've tried everything looking for this book title,any help would be greatly appreciated.

[Cupcakedoll]

[Will]

Definitely the wind singer series.

[Emrick]

Cupcakedoll wrote: ""
Thank you guys so much!

[Lobstergirl, au gratin]

(Shelved.)