Spirits of Ash and Foam

Welcome to the Prospero Keys (or as the locals call them: the Ghost Keys), the beautiful chain of tropical islands on the edge of the Bermuda Triangle where Rain Cacique lives. When Rain's maternal grandfather passed away, he left her his special armband: two gold snakes intertwined, clasping each other's tails in their mouths. Rain soon discovers that the armband is actually a zemi – a very powerful talisman created by the island's native Arawak Taino Indians – and that it allows Rain to see ghosts, including her own grandfather who is determined to help her uncover the Ghost Keys' hidden world of mystery and mysticism, intrigue and adventure.

Now, Rain Cacique's looking for a few answers — and the second zemi, a Taino relic that allows her to see dead people. But it's the first week of school, so she's pretty busy juggling teachers, homework, baby-sitting duties, new friends, missing tourist kids… and a vampire with a tribal twist.
Spirits of Ash and Foam is the second installment in Greg Weisman's Rain of the Ghosts series.