Ghost Towns by Bella Forrest

Now that Robin has discovered a lead on her daughter, all she can think about is tracking her down. And her birth parents—whom Robin never dreamed she’d have the opportunity to meet.

But when Robin and Jace return to the outside world, after gaining permission from Nathan, there have been worrying developments. Townships housing the poor are being emptied at an alarming rate, seemingly faster than ever before, and they have no idea why, or where the residents are being taken.

A personal mission quickly turns into something much greater as Robin and Jace follow the clues… leading to answers neither of them is prepared for.