Prince William and Princess Kate will be handing out the Earthshot Prizes on Friday evening, but ahead of their main event, the Princess of Wales went out on a solo engagement.
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The mum-of-three visited the Center on the Developing Child at Harvard University, the cause is close to her heart due to her ongoing work to highlight the importance of early years when it comes to later life outcomes. She also held discussions with researchers about ongoing recent advances in science can increase the impact of the ongoing work.
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The Princess of Wales has history with the institution, with it being linked to the Royal Foundation and the more recent Royal Foundation Centre for Early Childhood. She came well prepared for her visit, carrying with her a notebook full of ideas and questions for the researchers.
Upon arrival, the royal signed the guest book, which was also done by King Charles when he visited the institution back in 1986.
At the event, she looked as flawless as ever wearing a stylish dress from Emilia Wickstead and earrings from Lenique Louis.
She praised the work of those there, saying: "There is so much amazing work going on and we need to start sharing the learning and science and what can be done better and be improved to help children in the trajectory into adult life. It is frustrating because I'd like to be here for days."
After the trip, Kate went on a walkaround outside the venue meeting with crowds that had gathered. The royal took selfies with members of the public, and was even given a lovely bouquet of flowers. One fan even admitted that they had spent £870 to fly across the United States in order to greet the Princess.
The Harvard visit will not be her only outing of the day, as she is due to meet US president Joe Biden later on.
Kate will then unite with her husband for the Earthshot Awards, which is being hosted in Boston.
Meanwhile, William is undertaking an outing himself as he visits the John F. Kennedy Presidential Library and Museum.
He will be given a short tour by Ambassador Caroline Kennedy, and the visit will surely hold special significance for the Prince, as President Kennedy's Moonshot Project served as the inspiration for his own Earthshot.
During his tour, William will be shown pivotal photos taken during John F. Kennedy's tenure as President, ahead of a private lunch with representatives from the founding partner organisations for Earthshot.