"No Passengers Beyond This Point" by Gennifer Choldenko

Life is turned upside down when three siblings are forced to move. Their house has gone into foreclosure, and the bank is taking the house away. India, Finn and Switzerland, a.k.a. Mouse, are all named after countries their mom wanted to travel to. But times are harder now, there's no money to travel, and she is forced to send them to live with Uncle Red. Life is so unfair.

Uncle Red lives in Colorado, and India is put in charge of Finn and Mouse on the plane ride. All is going well, until the plane hits some serious turbulence. When they land, a car is waiting for them, and takes them to a strange city called Falling Bird. But there is no sign of Uncle Red anywhere. Everything in Falling Bird seems to be a little too perfect. They have whatever they desire, and people are so excited they are there. Certain things seem out of place, and they soon realize there are many questions left to be answered. Getting home, or even leaving Falling Bird, may not be as easy as they think.