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:

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:

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