She doubled back towards the child and shook his hand, before breaking out in a laugh as the little boy looked on, unsmiling.
A day after gathering for the youngest royal heir's special church service, Prince William, Kate Middleton, Prince Harry, and Meghan Markle helped celebrate the 100th anniversary of the Royal Air Force.
Her choice of Givenchy is an unsurprising one since she has become an ardent champion of the French fashion house under Claire Waight Keller's creative direction in recent months, and famously wore her custom design on her wedding day.
Queen Elizabeth and senior royals watched nearly 100 aircraft, from World War Two Spitfires to the newest stealth fighter jet fly over Buckingham Palace on Tuesday in a celebration to mark the 100th anniversary of Britain's Royal Air Force.
Prince Harry and Meghan Markle have hit the ground running in Ireland on their very first overseas tour as newlyweds.
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The boys remain in quarantine but some of their parents have been able to see their children through the glass. Shortly after the full rescue was announced, President Trump sent a congratulatory message.
A trio of F-35B Lightning II aircraft of 617 Squadron taking part in the RAF100 flypast over London to mark the centenary of the RAF.
Collier told MailOnline: "The bun is quickly becoming the Duchess's signature look, so it's no surprise to see her sporting this style at today's ceremony".
DOMINIC LIPINSKI/PA WIRE/PA IMAGES The family at Prince Louis' christening on July 9.
Meghan debuted her third outfit of the day, wearing a stunning belted black cocktail dress by designer Emilia Wickstead.
She will present a new Queen's Colour to the RAF in the forecourt of Buckingham Palace and make a brief speech before appearing on the balcony for the flypast.
Harry said he and Meghan hoped to reflect on some of the hard passages in the neighbouring islands' history when they visit a memorial to Ireland's Great Famine of the 1840's and the Gaelic sports stadium Croke Park.