Metropolitan Museum of Art. She married Edwin Schlossberg in 1986 and the marriage lasts. There are three children: Rose, Tatania, and John, named after JFK and now 15.

Caroline runs the Kennedy Library Foundation, is chairman of the American Ballet Theatre and is a director of the Legal and Education Fund of the civil rights group, the National Association for the Advancement of Coloured People.

There is speculation that the Kennedy clan wants to scotch the chances of the Clintons setting up a rival legacy. And there are questions over whether her intervention is a good thing: like JFK, Obama is more a man of image than of substance.

Caroline is due to step onto a Washington stage today with her uncle, Senator Ted Kennedy, to formally endorse Obama. For better or for worse, she has already done far more than that.