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Princess Kate attended husband Prince William's second annual Earthshot Prize Awards at the MGM Music Hall at Fenway in Boston on Dec. 2, 2022, wearing an emerald and diamond choker that previously belonged to her late mother-in-law, Princess Diana, with matching emerald and diamond earrings. The necklace was initially worn by Queen Mary in the early 1900s. Diana wore it as both a necklace and, notably, a headband (see her in it here). Diana donned the emerald necklace for the final time on her 36th birthday in 1997 (see it here) — less than two months before she died.
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Princess Kate — wearing a bright green dress by Solace London that was rented from HURR for less than $100 — and Prince William arrived at the future king's second annual Earthshot Prize Awards at the MGM Music Hall at Fenway in Boston on Dec. 2, 2022. She accessorized with emerald earrings and an emerald and diamond necklace that belonged to her late mother-in-law, Princess Diana. Earthshot guests were asked to focus on sustainability by wearing something recycled or vintage on the big night. The couple arrived in an electric vehicle, served plant-based food, reused the green carpet from the previous year's event and ensured no single-use plastics were used at the event, Boston's 7 News reported.
MORE: The best photos of Kate Middleton from her first months as the newly titled Princess of Wales
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Prince William, U.S. Ambassador to Australia Caroline Kennedy and her two youngest children — son Jack Schlossberg and daughter Tatiana Schlossberg — toured the John F. Kennedy Presidential Library and Museum in Boston on Dec. 2, 2022, the final day of the Prince of Wales' three-day visit with wife Princess Kate for his Earthshot Prize Awards.
MORE: The best photos from Prince William's second annual Earthshot Prize Awards
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Prince William and Caroline Kennedy — who's currently the U.S. ambassador to Australia, which is part of Britain's Commonwealth of Nations — inspected an exhibit at the John F. Kennedy Presidential Library and Museum in Boston on Dec. 2, 2022, the final day of his three-day visit with wife Princess Kate for his Earthshot Prize Awards.
MORE: The best photos from the first months of King Charles III's reign
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Prince William chatted with President Joe Biden outside the John F. Kennedy Presidential Library and Museum in Boston on Dec. 2, 2022, the final day of his three-day visit with wife Princess Kate for his Earthshot Prize Awards.
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Prince William and Princess Kate chatted with David Beckham — that's actress Catherine O'Hara in the background — at the Earthshot Prize Awards at the MGM Music Hall at Fenway in Boston on Dec. 2, 2022. Other celebrities who attended, performed or participated in the night include Rami Malek, Shailene Woodley, Ellie Goulding, Annie Lennox, Daniel Dae Kim, Chloe x Halle and more.
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Princess Kate, wearing a houndstooth dress by Emilia Wickstead, visited Harvard University in Cambridge, Massachusetts, on Dec. 2, 2022, in a solo outing on the final day of her three-day visit to Boston with husband Prince William for his Earthshot Prize Awards. She spent time at Harvard's Center on the Developing Child, which has a relationship with The Royal Foundation as well as her own Royal Foundation Centre for Early Childhood.
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Prince William and Princess Kate bundled up in coats as the spoke with Boston's Mayor Michelle Wu and Reverend Mariama White-Hammond during a walking visit to east Boston on Dec. 1, 2022, to see the changing face of the shoreline as the city contends with rising sea levels.
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Princess Kate bundled up in Gabriela Hearst knitwear and a chocolate brown Alexander McQueen coat as she spoke with Boston's Mayor Michelle Wu and Reverend Mariama White-Hammond during a walking visit to east Boston on Dec. 1, 2022, to see the changing face of the shoreline as the city contends with rising sea levels.
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Princess Kate, wearing a well-tailored wine-colored Rouland Mouret suit, arrived for a visit to Greentown Labs, North America's largest clean-tech incubator, in Somerville, Massachusetts, on Dec. 1, 2022, on day two of her three-day trip to Boston with husband Prince William.
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Princess Kate and Prince William visited Greentown Labs, North America's largest clean-tech incubator, in Somerville, Massachusetts, on Dec. 1, 2022, during their three-day trip to Boston.
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Princess Kate and Prince William met a boy dressed as a King's guard — who came bearing flowers for the Princess of Wales — during their visit to Greentown Labs, North America's largest clean-tech incubator, in Somerville, Massachusetts, on Dec. 1, 2022, on day two of the couple's three-day trip to Boston.
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Prince William and Princess Kate watched an NBA basketball game between the Boston Celtics and the Miami Heat at TD Garden in Boston on Nov. 30, 2022, during their three-day official visit to the States to celebrate the Prince of Wales' Earthshot Prize awards gala while in town. During the game, "both times William and Kate appeared on the @tdgarden big screen there were cheers but also some boos. Along with chants of 'USA, USA,'" ITV News Royal Editor Chris Ship tweeted alongside videos of the pair on the screen. "Some say it was expected at the Boston team @celtics with such strong Irish roots. But, still, not something the Royals get very often."
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Princess Kate and Prince William arrived at Logan International Airport in Boston on Nov. 30, 2022, after flying commercial on British Airways from London. The Prince and Princess of Wales are visiting Boston for three days to attend William's second annual Earthshot Prize Awards Ceremony, an event that celebrates those whose work is helping to repair the planet.
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Princess Kate kicked off Earthshot celebrations by lighting up Boston at Speaker's Corner by City Hall Boston, Massachusetts, on Nov. 30, 2022, on what turned out to be a rainy night. The Prince and Princess of Wales are visiting Boston to attend the second annual Earthshot Prize Awards Ceremony, an event that celebrates those whose work is helping to repair the planet. During their three-day trip, the royal couple is learning about the environmental challenges Boston faces as well as meeting those who are combating the effects of climate change in the area.
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Prince William and Princess Kate attended an NBA game between the Boston Celtics and the Miami Heat at TD Garden in downtown Boston on Nov. 30, 2022.
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Prince William and Princess Kate arrived at Logan International Airport in Boston on Nov. 30, 2022. The Prince and Princess of Wales are visiting Boston for three days to attend William's second annual Earthshot Prize Awards Ceremony, an event that celebrates those whose work is helping to repair the planet.
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Princess Kate met with Boston's Mayor Michelle Wu and her children at City Hall in Boston on Nov. 30, 2022.
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Prince William and Princess Kate arrived at Logan International Airport in Boston on a commercial British Airways flight on Nov. 30, 2022. The Prince and Princess of Wales are visiting Boston for three days to attend William's second annual Earthshot Prize Awards Ceremony, an event that celebrates those whose work is helping to repair the planet.
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Boston Mayor Michelle Wu, Massachusetts Governor-elect Maura Healey, Prince William, Princess Kate, Emilia Fazzalari and her husband — Boston Celtics owner Wyc Grousbeck — watched Jaylen Brown play during an NBA game between the Boston Celtics and the Miami Heat at TD Garden in downtown Boston on Nov. 30, 2022.
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Prince William and Princess Kate kicked off Earthshot celebrations by lighting up Boston green at Speaker's Corner by City Hall in Boston, Massachusetts, on Nov. 30, 2022. The Prince and Princess of Wales are visiting Boston to attend the second annual Earthshot Prize Awards Ceremony, an event that celebrates those whose work is helping to repair the planet.
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Prince William and Princess Kate posed with Boston's Mayor Michelle Wu and her husband, Conor Pewarski, and their kids to kick off Earthshot celebrations by lighting up Boston green at Speaker's Corner by City Hall in Boston on Nov. 30, 2022, on a rainy night.
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During the rainy first night of their three-day trip to Massachusetts, Prince William and Princess Kate kicked off Earthshot celebrations by lighting up Boston green at Speaker's Corner by City Hall in Boston, Massachusetts, on Nov. 30, 2022.