Title says it all

When Jonathan, Maysilee, Tammi, Max, Luther and Pearla Harcourt get lost on a stormy day in the woods while visiting family in a small village in Italy over spring break, the last thing that they expect to find is twelve year old twins, Willow and Cara Vance, two homeless girls living in a tree house who used to live in the village. Curious to how the twins got there, the oldest Harcourts, Rylie and Mary Grace (along with their mother) tackle the mystery with ease. But when they do so and it's revealed that the twins are the kids's long believed to be dead cousins, things take a turn. Upon revealing the discovery to the twins, Cara runs away. Upon returning to Italy for the summer, the Harcourts make it their mission to help Willow and her little sister Analee find Cara. Along with their faithful dog Spotty of course! (This is more of a 7-14 year old age range story, for the record, so it's kinda kiddy, but please read anyway!)