Meghan Markle is continuing her busy royal week.
On Tuesday, she joined Prince Harry, Queen Elizabeth, Prince William, Kate Middleton, Prince Charles, Camilla, Duchess of Cornwall and other members of the royal family to mark the 100th birthday celebrations of the Royal Air Force.
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The day after the christening of Prince Louis, the family attended a Westminster Abbey service to honor the world’s first independent air force, which was set apart from the British Army and Royal Navy on April 1, 1918.
Meghan wore an Audrey Hepburn-inspired bespoke dark navy Dior dress with a boatneck neckline (her go-to style!), paired with a Stephen Jones fascinator, while Kate opted for another Alexander McQueen creation — the royal mom of three also wore McQueen (her wedding dress designer) to Louis’ christening. She topped it off with a matching hat by Sean Barrett.
Queen Elizabeth and Prince Philip were noticeably absent from Monday’s christening after the palace announced that the royal couple would not be in attendance. The decision, which was likely due to her busy schedule, was “mutually agreed” between the 92-year-old monarch and William and Kate “some time ago,” a palace source tells PEOPLE.
Palace sources say there is no cause for any concern about the health of either her or Philip, 97, and the Queen appeared in good spirits at Tuesday’s event. Following the service, the Queen and Charles, 69, stood on the forecourt of Buckingham Palace to present a new Queen’s Colour to the Royal Air Force.
Kate, who took over from Prince Philip as Honorary Air Commandant of the Air Cadets in December 2015, attended the event despite still being on maternity leave. She also wore the diamond Dacre Brooch she received for being patron of the air cadets.
During his military career, William served in the RAF Search and Rescue service in North Wales and was joined briefly by his brother at RAF Shawbury, where they both trained to fly helicopters.
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After a short speech, the Queen headed back into the palace, where Meghan and the rest of the family were set to join her on the balcony to observe a thunderous flypast. The event is to feature 100 aircraft — including jet fighters, a WWII Lancaster bomber and the ceremonial Red Arrows — while below there will be a Feu de Joie, or mass rifle salute.
Meghan made her debut on the famous balcony for the annual Trooping the Colour in June, which celebrates the Queen’s birthday.
Soon after the flypast, Meghan and Harry — the new Duke and Duchess of Sussex — will head to Dublin for their first official overseas visit since their May 19 wedding. They are scheduled to touch down in Ireland around noon ET.