Harry was recently reunited with Kate, William and the rest of the royals for the first time in over a year at his grandfather Prince Philip's funeral on April 17.
Meanwhile, Meghan, who is pregnant with the couple's second child, a baby girl, was advised by her doctor not to travel. She and their young son Archie, who is due to turn 2 on May 6, stayed in California at their family home.
William and Harry walked in the funeral procession behind their grandfather's coffin, kept apart by their cousin Peter Phillips. But the brothers later had a casual chat after exiting the chapel following the service.
Historian Robert Lacey told the outlet that "the procession choreography, in retrospect, was a mistake".
"As we saw, they could have walked side-by-side quite happily after all. What pleased me afterward was that it all seemed so totally natural, and they drifted to each other like the old days."
The two princes were then seen chatting along with Kate, 39, as they left St George's Chapel in Windsor Castle together, continuing to chat before Kate dropped back to chat with Sophie, Countess of Wessex.
And to celebrate their tenth wedding anniversary, William and Kate released two new portraits taken last week.
They also shared a sweet home video offering a rare glimpse into their family life with Prince George, Princess Charlotte and Prince Louis.