The eleven-year-old Deirdre suffers from an incureable heart trouble. For two years, her parents Eugene and Ruth have consulted heart specialists - but without any success. Now they have gone to Mahone Bay in Canada, to arrange for her last days as pleasant as possible. The nine-year-old neighbour boy Phillip is the only one who brings a little happiness into the home, because Deirdre knows exactly whats wrong with her. After she suffered from an acute attack and the end comes faster than everybody had thought, Deirdre and Phillip succeed in celebrating the twelfth birthday of the girl as a day of joy.