The two dazzled in very different but equally gorgeous looks, with Meghan wowing in a designer and cut she has never worn before.
The day after the christening of Prince William and Kate Middleton's third child, Prince Louis, the proud parents, accompanied by Prince Harry and his new wife Meghan Markle, attended the 100th birthday celebrations of the Royal Air Force.
The Duchess kept up her signature nude lip look as well.
The visit is their first trip overseas as a married couple, following their wedding in May.
The tribute to the RAF, which became the world's first independent air force when it was founded as a separate entity from the British Army and Royal Navy in 1918, began with a service at Westminster Abbey.
Kate Middleton and Archbishop of Canterbury joke about sleeping Louis
See how Prince Louis has grown! Max Mumby/Indigo via Getty Images Prince Louis was born on April 23, 2018 in London , England. Louis is set to wear the same christening gown used by his siblings, Prince George and Princess Charlotte .
Grasping Prince Harry's hand, the new Duchess of Sussex cut a stylish form in a flattering shade of olive green, which not only complimented her skin tone, but held a significant meaning.
When Meghan and Harry stepped out at a casual reception in London this week, her hair was pulled back into a sleek low bun.
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.
However neither Prince Harry nor Meghan were named among Louis' six godparents, with the honour going to Guy Pelly, who was once dubbed the "court jester", family friend Nicholas van Cutsem and William's school pal Harry Aubrey-Fletcher.