It’s just a typical family weekend outing at grandma’s house—except that the family happens to be Princess Grace and Prince Rainier of Monaco and their three royal children, and grandma’s place happens to be a castle in the woods, Le Château de Marchais in the Ardennes mountains. As often as possible the couple and their children, Stephanie, Caroline and Albert, take time out from school schedules, camera-clicking paparazzi and princely protocol to have fun as the Grimaldis—Prince Rainier’s family name. Back in Monaco, in addition to the regular business of running the 467-acre principality, his and her serene highnesses are making preparations for the celebration of two landmark events. In April they will mark their 18th wedding anniversary, and in May, the entire principality will whoop it up on the 25th anniversary of Prince Rainier’s ascension to the throne. Then they’ll start planning for Caroline’s coming-out party, which promises to be one of the most glittering events in the 1975 European social calendar.