Ways to see a ghost - Emily Diamand

Isis, the daughter of a charlatan psychic, can see ghosts - including
that of her little sister, Angel. Gray is the son of a UFO-chasing
conspiracy theorist. The two teenagers are forced together when their
parents start dating and after a reluctant start, their friendship develops and
Isis confesses her secret ability to Gray. But when Isis' mum is
inducted into an elite psychic society, run by charismatic Philip
Syndal, Isis discovers there are sinister intentions beneath Philip's
charm. She and Gray find themselves in grave danger and Isis is forced
to use her
powers to save them both.