Prince William and Princess Kate reunite with children following royal tour

The Prince and Princess of Wales have reunited with their three young children after they landed back in the United Kingdom following their trip to America.

PHOTOS: Royal Style Watch: Princess Kate's impeccable Boston tour outfits you need to see

The royal couple headed straight to the airport following the end of the Earthshot Prizes and landed back in London on Saturday morning. The couple would not have wasted any time in reuniting with their children back in Windsor. The royal children have been in the care of their nanny, Maria Teresa Turrion, who has been with the family since 2014.

WATCH: The Prince and Princess of Wales arrive at Earthshot ceremony

Kate and William have been away from Prince George, Princess Charlotte and Prince Louis for three days as they headed to Boston for the second Earthshot Awards.

DISCOVER: Princess Kate's show-stopping major first everyone is talking about

PHOTOS: Princess Kate just styled Diana's heirloom totally different from the late royal

On the first day of their visit to Boston, the couple surprised onlookers as they took their seats courtside to watch Boston Celtics take on Miami Heat.

On the second day, William and Kate took in Piers Park and learned about the history of the area now threatened by rising sea levels. However, the freezing temperatures saw William put his hands in his pockets, laughing that "when I can feel them again they come back out".

They visited Greentown Labs in the nearby town of Somerville before meeting those who had been helped by Roca, a non-profit organisation supporting disadvantaged young people in the neighbouring city of Chelsea. They also undertook their first public walkabout in the city where they greeted one woman who was reduced to tears.

Prince William and Kate at the Earthshot awards
Prince William and Kate at the Earthshot awards

The royals were in Boston

The third day saw them on separate engagements, with Kate visiting the Center on the Developing Child at Harvard University.

Meanwhile, ahead of a meeting with President Joe Biden, William visited the John F. Kennedy Presidential Library and Museum.

SEE: Watch the sweet moment Princess Kate and Prince William almost broke 'royal protocol'

SHOP: Princess Kate's bright green dress - 5 lookalikes to recreate the look

He was given a short tour by Ambassador Caroline Kennedy, and the visit held special significance for the Prince, as President Kennedy's Moonshot Project served as the inspiration for his own Earthshot.

They then reunited for the main Earthshot event, which proved to be a star-studded affair with Catherine O'Hara and David Beckham in attendance, alongside a virtual performance from Billie Eilish.

Make sure you never miss a ROYAL story! Sign up to The Royal Explainer newsletter to receive your weekly dose of royal features and other exclusive content straight to your inbox.