Nathalie and David have been good and dutiful children to their parents. Now that they are both settled, with partners and children of their own, they are still close. Good friends. Brother and sister. Except that they aren't — brother and sister, that is. Each of them had been adopted when their loving parents, Lynne and Ralph, found that they couldn't have children of their own. And Nathalie and David have always sworn to each other, and to their families, that it didn't matter. But it did matter, of course, and when Nathalie discovers a deep need to trace her birth parents, she insists that David makes the same journey. She also discovers that sometimes the answers — to who we are and where we come from — are harder than the questions...