Camelot met Swan Lake at the New York Metropolitan Opera House Monday night, as Caroline Kennedy Schlossberg, 43, served as co-chairman and hostess of the 30th anniversary benefit gala of the American Ballet Theater, reports Besides Schlossberg and her husband, Edwin, the society crowd also included New York’s social empress Brooke Astor, 99, and two of Caroline’s aunts: Lee Radziwill, 68 (sister of Caroline’s late mother, Jacqueline Kennedy Onassis), as well as Patricia Kennedy Lawford, 76, and Jean Kennedy Smith, 73 (both sisters of Caroline’s late father, President John F. Kennedy). “I can tell it’s spring,” a very composed Caroline, wearing a full-length red gown, told the crowd of thousands inside the opera house, “because the American Ballet Theater has returned to New York.” The appearance marked the former First Daughter’s second highly visible New York outing in as many weeks. The previous Monday, she attended the opening of the Metropolitan Museum of Art exhibit, “Jacqueline Kennedy: The White House Years.”