Now and Forevermore Arabella

Found abandoned in Colorado a mall when she was too young to say how she got there, the little three-year-old girl wearing a bracelet with the name "Amanda" on it doesn't know anything about herself, not how she came to be left there, not who her parents are, and not even her full real name.  Right from the start she didn't believe her name was "Amanda," no matter what the bracelet said, although no one at the foster care agency that took charge of her would listen when she tried to tell them that ...

Nine years of living in foster care later the truth finally comes to light.  "Amanda's" latest social worker arrives at her school to give her astonishing news: she's not an actual orphan at all!  It turns out she was accidentally kidnapped in Florida when one of the antique cars her father sells was stolen after an outdoor car show while she was in it.  DNA testing proves she's really a missing girl named Arabella Prescott, and her life changes for the better when her terrific parents and adoring little sister arrive to take her home to the island of Farris Key, where just about everybody she meets is thrilled to have her back.  After so many years of trying not to be noticed while she was bounced around from one temporary home to another, Arabella, as she now and forevermore wants to be called again, becomes more boisterous by the day as she settles in with her newfound family, goes to a great school with her sister and cousins and meets new friends. 

Yet Arabella is back living on the very island from which she was kidnapped in the first place, so alongside the family's joy at their reunion there are some very disturbing concerns.  Are the kidnappers, who were never found, island people too?  Who is the odd person who seems to keep watching their house from the beach across the street?  What exactly happened to cause the authorities in Colorado not to figure out Arabella's identity when there were people all over Florida looking for her? 

And why does a certain nearby house keep giving Arabella the creeps?