Last September, Daniel Wildenstein’s family celebrated his 80th birthday with a party at the two-star restaurant Laurent, one of Paris’s most fashionable spots. It was an intimate dinner, for about 70 guests, to which Daniel’s 64-year-old second wife, Sylvia, had invited only her husband’s closest friends and his family, whose members had flown in for the occasion from New York, Montreal, and Palm Beach, some of them on the family’s private Gulfstream IV. Daniel’s two sons, Alec, 57, and Guy, 52, and Guy’s wife, Kristina, were there, as were all six of his grandchildren. Most of the friends in attendance that night were from the horse-racing world, trainers and jockeys who had worked with the Wildensteins over the years. Horse racing was the old man’s passion, and his stable, Allez France, is considered among the best in Europe.