Time Runs Out — Julia Kane

When her eleven-year-old son Bing is badly burned in a train accident, Christine Ross is told by the plastic surgeon that only one thing can save the boy's life - a skin-graft from an identical twin. The information plunges Christine into a twofold crisis: To reveal to her unsuspecting husband the truth that he is not Bing's father. To find, somewhere in the wide world, the missing twin - with only two weeks in which to do it. As time runs out...