Kathleen Cavendish, Marchioness of Hartington (born 1920)

Kathleen Agnes Cavendish, Marchioness of Hartington, also known as "Kick" Kennedy, was an American socialite. She was the second daughter of Joseph P. Kennedy Sr. and Rose Fitzgerald, a sister of U.S. President John F. Kennedy and Senators Robert F. Kennedy and Ted Kennedy, and the wife of the Marquess of Hartington, heir apparent to the 10th Duke of Devonshire.