New from Harlequin Teen: The First to Know by Abigail Johnson.
About the book, from the publisher:
Dana Fields's father never knew his parents. When Dana secretly does a DNA test for her dad, hoping to find him some distant relatives for his birthday, her entire world implodes. Instead of a few third cousins, Dana discovers a half brother her age whose very existence means her parents' happy marriage is a lie.Visit Abigail Johnson's website.
Dana's desire to know her half brother, Brandon, and the extent of her dad's deception, clashes with her wish not to destroy her family. When she sees the opportunity to get to know Brandon through his cousin, the intense yet kind Chase, she takes it. But the more she finds out about Brandon, her father's past and the irresistible guy who'll never forgive her if he discovers the truth, the more she sees the inevitable fallout from her own lies. With her family crumbling around her, Dana must own up to her actions and find a way to heal the breach—for everyone—before they're torn apart for good.
--Marshal Zeringue