Meghan Markle and Prince Harry attend service with Prince William and Kate Middleton: Pics!

The fab four are back!

Just one day after the christening service of Prince Louis, Meghan Markle, Prince Harry, Prince William, and Kate Middleton made yet another appearance at Westminster Abbey in London on Tuesday morning.

The fierce foursome attended the Royal Air Force service, marking 100 years of the organization.

For the occasion, the Duchess of Sussex, 36, donned a chic black A-line dress with long sleeves that cut off below the knee. She paired the look with cream-colored heels and a spiral-shaped black fascinator. Her handsome hubby, 33, sported his military uniform.

Middleton, 36, wore an ice blue fitted dress with a matching fascinator and tan heels. She looked trim and fit just two months after giving birth to her third child, son Prince Louis. Prince William, 36, was also by her side in full military garb.

See photos from the family outing:

18 PHOTOS
Royals honor 100 years of Royal Air Force: Pics!
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Royals honor 100 years of Royal Air Force: Pics!
The Duke and Duchess of Cambridge and the Duke and Duchess of Sussex arrive at a service at Westminster Abbey, London, to mark the centenary of the Royal Air Force. (Photo by Steve Parsons/PA Images via Getty Images)
The Duke and Duchess of Cambridge and the Duke and Duchess of Sussex arrive at a service at Westminster Abbey, London, to mark the centenary of the Royal Air Force. (Photo by Steve Parsons/PA Images via Getty Images)
The Duchess of Cambridge attends a service at Westminster Abbey, London, to mark the centenary of the Royal Air Force. (Photo by Steve Parsons/PA Images via Getty Images)
The Duchess of Sussex leaves a service at Westminster Abbey, London, to mark the centenary of the Royal Air Force. (Photo by Steve Parsons/PA Images via Getty Images)
Queen Elizabeth II attends a service at Westminster Abbey, London, to mark the centenary of the Royal Air Force. (Photo by Steve Parsons/PA Images via Getty Images)
LONDON, ENGLAND - JULY 10: Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge attend a service to commemorate The Royal Air Force's 100th Birthday at Westminster Abbey on July 10, 2018 in London, England. (Photo by Simon Dawson - WPA Pool/Getty Images)
The Duke and Duchess of Sussex arrive at a service at Westminster Abbey, London, to mark the centenary of the Royal Air Force. (Photo by Steve Parsons/PA Images via Getty Images)
Britain's Camilla, Duchess of Cornwall (L) arrives for a service to mark the centenary of the Royal Air Force (RAF) at Westminster Abbey in central London on July 10, 2018. (Photo by Chris J Ratcliffe / AFP) (Photo credit should read CHRIS J RATCLIFFE/AFP/Getty Images)
The Prince of Wales, the Duchess of Cornwall and the Duke and Duchess of Cambridge leave a service at Westminster Abbey, London, to mark the centenary of the Royal Air Force. (Photo by Steve Parsons/PA Images via Getty Images)
Britain's Camilla, Duchess of Cornwall (L) and Britain's Catherine, Duchess of Cambridge leave a service to mark the centenary of the Royal Air Force (RAF) at Westminster Abbey in central London on July 10, 2018. (Photo by Chris J Ratcliffe / AFP) (Photo credit should read CHRIS J RATCLIFFE/AFP/Getty Images)
Britain's Queen Elizabeth II leaves a service to mark the centenary of the Royal Air Force (RAF) at Westminster Abbey in central London on July 10, 2018. (Photo by Chris J Ratcliffe / AFP) (Photo credit should read CHRIS J RATCLIFFE/AFP/Getty Images)
LONDON, ENGLAND - JULY 10: Meghan, Duchess of Sussex attends a service to commemorate The Royal Air Force's 100th Birthday at Westminster Abbey on July 10, 2018 in London, England. (Photo by Simon Dawson - WPA Pool/Getty Images)
LONDON, ENGLAND - JULY 10: Queen Elizabeth II, Meghan, Duchess of Sussex, Prince Harry, Duke of Sussex, Prince William Duke of Cambridge and Catherine, Duchess of Cambridge watch the RAF 100th anniversary flypast from the balcony of Buckingham Palace on July 10, 2018 in London, England. (Photo by Paul Grover - WPA Pool/Getty Images)
LONDON, ENGLAND - JULY 10: Queen Elizabeth II, Meghan, Duchess of Sussex, Prince Harry, Duke of Sussex, Prince William Duke of Cambridge and Catherine, Duchess of Cambridge watch the RAF 100th anniversary flypast from the balcony of Buckingham Palace on July 10, 2018 in London, England. (Photo by Paul Grover - WPA Pool/Getty Images)
LONDON, ENGLAND - JULY 10: LONDON, ENGLAND - JULY 10: Queen Elizabeth II and Meghan, Duchess of Sussex watch the RAF 100th anniversary flypast from the balcony of Buckingham Palace on July 10, 2018 in London, England. (Photo by Paul Grover - WPA Pool/Getty Images)
(left to right) The Duchess of Sussex, Duke of Sussex, Duke of Cambridge and Duchess of Cambridge on the balcony at Buckingham, Palace where they watched a Royal Air Force flypast over central London to mark the centenary of the Royal Air Force. (Photo by Victoria Jones/PA Images via Getty Images)
(left to right) The Prince of Wales, Duke of York, Duchess of Cornwall, Queen Elizabeth II, Duchess of Sussex, Duke of Sussex, Duke of Cambridge and Duchess of Cambridge on the balcony at Buckingham, Palace where they watched a Royal Air Force flypast over central London to mark the centenary of the Royal Air Force. (Photo by Victoria Jones/PA Images via Getty Images)
(L-R) Britain's Sophie, Countess of Wessex, Britain's Prince Charles, Prince of Wales, Britain's Camilla, Duchess of Cornwall, Britain's Queen Elizabeth II, Britain's Meghan, Duchess of Sussex, Britain's Prince Harry, Duke of Sussex, Britain's Prince William, Duke of Cambridge and Britain's Catherine, Duchess of Cambridge stand on the balcony of Buckingham Palace on July 10, 2018 to watch a military fly-past to mark the centenary of the Royal Air Force (RAF). - The Queen and members of the royal family took part a series of engagements on July 10 to mark the centenary of the Royal Air Force. (Photo by Tolga AKMEN / AFP) (Photo credit should read TOLGA AKMEN/AFP/Getty Images)
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The younger royals attended the event alongside Queen Elizabeth, who was noticeably absent from Prince Louis’ christening on Monday. The Queen looked to be in good spirits on Tuesday, wearing a periwinkle blue coat dress with light blue accents and a matching hat.

Buckingham Palace confirmed to ET on Monday that Queen Elizabeth and Prince Philip would not be attending the christening service, noting that it was a fairly small service, so guests would only include immediate family and godparents. The Palace also told ET that the decision was “mutually agreed upon some time ago” that the Queen and the Duke of Edinburgh would not be attending.

Harry and Meghan, however, were there to lend their support to their new nephew. The Duke and Duchess of Sussex will head straight from Tuesday’s morning service in London to Dublin, Ireland, where they will begin a two-day tour of the country.

“The fact that Harry and Meghan have been asked by the Foreign Office to go to Ireland shows just how much faith the Queen has in both of them as working royals,” Katie Nicholl, the author of Harry: Life, Loss, and Love, told ET of the trip. “The Queen would have approved that trip, she would have made sure she was happy with the itinerary.

RELATED: See photos from Prince Louis' christening:

15 PHOTOS
Prince Louis' christening
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Prince Louis' christening
LONDON, ENGLAND - JULY 09: Princess Charlotte and Prince George hold the hands of their father, Prince William, Duke of Cambridge, as they arrive at the Chapel Royal, St James's Palace, London for the christening of their brother, Prince Louis, who is being carried by their mother, Catherine, Duchess of Cambridge on July 09, 2018 in London, England. (Photo by Dominic Lipinski - WPA Pool/Getty Images)
The Duke and Duchess of Cambridge with their children Prince George, Princess Charlotte and Prince Louis after Prince Louis's christening at the Chapel Royal, St James's Palace, London.
The Duke and Duchess of Cambridge with their children Prince George, Princess Charlotte and Prince Louis after Prince Louis's christening at the Chapel Royal, St James's Palace, London.
The Duke of Cambridge with Prince George and Princess Charlotte after Prince Louis's christening at the Chapel Royal, St James's Palace, London.
Britain's Catherine, the Duchess of Cambridge, carries Prince Louis as they arrive for his christening service at the Chapel Royal, St James's Palace, London, Britain, July 9, 2018. Dominic Lipinski/Pool via REUTERS
Britain's Catherine, the Duchess of Cambridge, carries Prince Louis as they arrive for his christening service at the Chapel Royal, St James's Palace, London, Britain, July 9, 2018. Dominic Lipinski/Pool via REUTERS
Britain's Catherine, the Duchess of Cambridge, carries Prince Louis as they arrive for his christening service at the Chapel Royal, St James's Palace, London, Britain, July 9, 2018. Dominic Lipinski/Pool via REUTERS
LONDON, ENGLAND - JULY 09: Catherine, Duchess of Cambridge carries Prince Louis as they arrive for his christening service at St James's Palace on July 09, 2018 in London, England. (Photo by Dominic Lipinski - WPA Pool/Getty Images)
The Duke and Duchess of Sussex depart after attending the christening of Prince Louis at the Chapel Royal, St James's Palace, London.
The Duke and Duchess of Cambridge with their children Prince George, Princess Charlotte and Prince Louis after Prince Louis's christening at the Chapel Royal, St James's Palace, London.
Pippa Middleton and her husband James Matthews arriving for the christening of Prince Louis, the youngest son of the Duke and Duchess of Cambridge at the Chapel Royal, St James's Palace, London.
The Prince of Wales and the Duchess of Cornwall arriving for the christening of Prince Louis, the youngest son of the Duke and Duchess of Cambridge at the Chapel Royal, St James's Palace, London.
Britain's Prince Harry and Meghan, the Duchess of Sussex, leave the chapel after the christening of Prince Louis at the Chapel Royal, St James's Palace, London, Britain, July 9, 2018. Dominic Lipinski/Pool via REUTERS
James Matthews arrives for the christening of Prince Louis, the youngest son of the Duke and Duchess of Cambridge at the Chapel Royal, St James's Palace, London, Britain, July 9, 2018. Dominic Lipinski/Pool via REUTERS
Pippa Middleton and her husband James Matthews, arrive for the christening of Prince Louis, the youngest son of the Duke and Duchess of Cambridge at the Chapel Royal, St James's Palace, London, Britain, July 9, 2018. Dominic Lipinski/Pool via REUTERS
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