Britain's Camilla, center, Duchess of Cornwall, and Zara Phillips, right, react as Wishfull Thinking falls unseating jockey Richard Johnson during The Queen Mother Champion Chase at the Cheltenham Festival horse racing meet in Gloucestershire, western England on March 14.

Wishfull Thinking , left, falls, unseating jockey Richard Johnson during the Queen Mother Champion Steeple Chase at the Cheltenham Festival horse racing meet in Gloucestershire, western England on March 14.

Richard Johnson riding Wishful Thinking falls during The sportingbet.com Queen Mother Champion Steeple Chase at Cheltenham racecourse on March14, in Cheltenham, England.

Richard Johnson riding Wishful Thinking falls during The sportingbet.com Queen Mother Champion Steeple Chase at Cheltenham racecourse on March14 in Cheltenham, England.

Britain's Prince Charles and Camilla, Duchess of Cornwall react as their car is attacked, in London, Thursday, Dec. 9. Angry protesters in London have attacked a car containing Prince Charles, the heir to the British throne, and his wife Camilla, Duchess of Cornwall. An Associated Press photographer saw demonstrators kick the car in Regent Street, in the heart of London's shopping district. The car then sped off. Charles' office, Clarence House, confirmed that "their royal highnesses' car was attacked by protesters on the way to their engagement at the London Palladium this evening, but their royal highnesses are unharmed."

General view of broken window and thrown paint damage to Prince Charles and Camilla, Duchess of Cornwall's car which occurred en route to the Royal Veriety Performace at the Palladium on December 9 in London, England.

General view of broken window and thrown paint damage to Prince Charles and Camilla, Duchess of Cornwall's car which occurred en route to the Royal Veriety Performace at the Palladium on December 9 in London, England.