The Gaps by Leanne Hall
What does it mean to be the one left behind?
When sixteen-year-old Yin Mitchell is abducted, the news reverberates through the whole Year Ten class at Balmoral Ladies College. As the hours tick by, the girls know the chance of Yin being found alive is becoming smaller and smaller.
Police suspect the abduction is the work of a serial offender, with none in the community safe from suspicion. Everyone is affected by Yin’s disappearance—even scholarship student Chloe, who usually stays out of Balmoral drama, is drawn into the maelstrom. And when she begins to form an uneasy alliance with the queen of Year Ten, Natalia, things get even more complicated.
Looking over their shoulders at every turn, Chloe and Natalia must come together to cope with their fear and grief as best they can. A tribute to friendship in all its guises, The Gaps is a moving examination of vulnerability and strength, safety and danger, and the particular uncertainty of being a young woman in the world. -goodreads