San Francisco Frontiers - Cambridge kids step out at first Trooping the Colour

The royal family traditionally appears on the balcony of Buckingham Palace to wave to crowds after the Trooping the Colour military parade.

On Thursday, Queen Elizabeth II's great-grandson -- fifth in line to the throne -- acted much like any other child his age.

He held his ears and appeared to yell as more than 70 military aircraft thundered overhead in a ceremonial fly-past.

At other points he jumped up and down and waved at the planes, which included the Royal Air Force Red Arrows display team trailing red, white and blue smoke.

Louis also pulled a face, fingers in his mouth, which prompted a quiet word from his mother, perhaps about the wind changing direction.

At other points, he slouched on the gold-braided red velvet covering the balustrade.

The 96-year-old queen, however, didn't seem to mind, breaking a smile as she took in the crowds for the first of four days of celebrations to mark her historic Platinum Jubilee.

Louis, his seven-year-old sister Princess Charlotte, and brother Prince George, aged eight, played a high-profile role in the day's events.

The children of the Duke and Duchess of Cambridge -- Prince William and his wife Kate -- travelled to Horseguards Parade by carriage with their mother, and grandfather Prince Charles' wife Camilla.

It was their first Trooping the Colour appearance, and they took the opportunity to practise a major royal duty -- waving to the crowds.

Louis, whose sailor suit was similar to that worn by his father in 1985, sat between his big brother and sister, who at one point could be seen pushing his arm down when he was mid-wave.

At Horseguards, the children peered out of the window of the Duke of Wellington's former office.

K.Gray--SFF