The Duchess of Cambridge marked the occasion on Jan. 9.
The royal family is celebrating a special milestone. In honor of Kate Middleton’s 40th birthday on Jan. 9, the official Instagram account marked the occasion with a series of throwback pictures featuring the Duchess of Cambridge with Queen Elizabeth.
“Wishing The Duchess of Cambridge a very happy 40th birthday today,” the Royal Family account captioned the photos.
The photo carousel begins with a picture of Middleton sitting next to the queen during an engagement in 2012. In the follow up picture, the Duchess, her husband Prince William and their two older children, Prince George and Princess Charlotte stand next to the 95-year-old monarch during the 2016 Trooping the Colour.
Rounding out the photo tribute, is a picture of Middleton, the queen and Camilla, Duchess of Cornwall.
Ahead of her royal’s big day, Kensington Palace released three new portraits on Jan.8. According to the palace, the photos were taken in November at Kew Gardens by photographer Paolo Roversi.
In the portraits, the Duchess made special nods to her late mother-in-law Princess Diana and Queen Elizabeth.
In the lead photo, where the Duchess wears a ruffled shoulder gown, she wears a pair of pearl drop earrings that once belonged to her late mother-in-law. Kate shows off the earrings in a second black and white photo. In the third portrait, the Duchess wears a red satin off-the-shoulder gown and puts a pair of diamond earrings that belonged to the 95-year-old royal on display.
The new portraits will become a part of the collection of the National Portrait Gallery, which is set to reopen in 2023. The photos will be featured as part of the gallery’s “Coming Home” project. According to the palace it will be dubbed as "a nationwide initiative which sees portraits of well-known individuals being sent to locations which they are closely associated with."
Middleton, who is a patron of the gallery, selected three destinations that have a special meaning to her. Berkshire in South England, St. Andrews in Scotland and Anglesey, an island off the coast of Wales.
Middleton’s birthday celebrations are set to be a little more low-key this year. According to royal expert Kate Nicholl, the occasion may include those closest to the royal.
"I think we are going to see the duchess celebrate her 40th -- it is a milestone birthday, it's an important birthday -- and I think there will be a celebration, but I think it will be a celebration for family and for close friends," Nicholl said.
"There was talk of a big party which has apparently been downscaled because of COVID and because of the restrictions. But I suspect that Kate is probably happier having something a little bit more low-key. She had a big 21st birthday but I think that was the last big birthday that she really, really celebrated."