On a cold Friday evening, Rebecca and her husband Jack's doorbell rings. Outside is a woman who introduces herself as Jack's ex-girlfriend Cara. And she's holding the hand of a shivering, blue-eyed, four-year-old girl. Who she claims is Jack's daughter.

Rebecca is shocked to discover he has a child from his last relationship--one he hadn't known about. Especially since becoming parents isn't part of their life plan. But Cara needs them. Because she has a devastating secret that she can't tell anyone yet. Not even her daughter. A secret with the power to change all of their lives, and one that forces Rebecca to ask herself: Could she find it in herself to welcome her husband's child into her home, and into her heart?