Can You Spot Prince William's Sly Tributes to Kate Middleton in Kensington Palace?

Kensington Palace Prince William chatting with Sadiq Khan at Kensington Palace

Even when royal duties keep them apart, Prince William always keeps a few sweet reminders of Kate Middleton nearby.

A photo of the Duke of Cambridge's recent meeting with London Mayor Sadiq Khan about his upcoming Earthshot Prize celebration revealed that William, 39, keeps a copy of Kate's book Hold Still: A Portrait of Our Nation in 2020 on the coffee table in an office at Kensington Palace where he welcomes dignitaries.

Released in May, Hold Still features 100 portraits reflecting the many different faces of individual experiences amid the COVID pandemic. Proceeds from the book raised will be split between leading mental health charity Mind and the National Portrait Gallery.

Just over Khan's shoulder, there is also a framed photo of William and Kate's 2010 engagement announcement, when the soon-to-be Duchess of Cambridge wowed in a striking blue Issa dress complementing her sapphire engagement ring once worn by Princess Diana.

Though some pandemic restrictions remain in place in the U.K., the royals' schedules have been ramping up in recent weeks, with several in-person events with both domestic and global leaders.

Jack Hill - WPA Pool / Getty Prince Charles, Camilla, Queen Elizabeth, Prince William and Kate Middleton

On June 11, William and Kate, 39, joined Queen Elizabeth, Prince Charles and Camilla, Duchess of Cornwall for a reception with dignitaries at the G-7 economic summit.

A few days later, the Queen, 95, welcomed Australian Prime Minister Scott Morrison to Windsor Castle for her first in-person audience in more than a year, and Morrison informed the Queen she was "quite the hit."

"Everyone was talking about you at dinner the next night," he said.

"Oh, Lord," the Queen replied. "Were they really?"

"They were," Morrison said. "They were thrilled to see you."

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And based on a few of the Queen's recent engagements, it would seem that she and her grandson, William, share a subtle sentimental streak and devotion to family.

In a virtual meet with the Ambassador from the Republic of South Sudan on June 8, she wore a cherished butterfly brooch in tribute to late husband Prince Philip, who died in April and would have turned 100 just two days after she wore the brooch.

Dominic Lipinski - WPA Pool/Getty Prime Minister Boris Johnson and Queen Elizabeth

Then, this past Wednesday, the Queen welcomed British Prime Minister Boris Johnson back to Buckingham Palace for their first in-person audience since the country went into lockdown amid the COVID pandemic.

Photos from the conversation showed that she has a rare shot of Meghan Markle and Prince Harry framed next to a bouquet of flowers. The picture was taken to celebrate their engagement, although it was never officially released to the public and seen only in the background of other photos by eagle-eyed fans.