The afternoon tea party is taking place in the apartment of the Duke and Duchess of Cambridge.
One of the first guests to arrive was one of George's four godfathers, Jamie Lowther-Pinkerton, the former principal private secretary of Prince William and the Duchess, née Kate Middleton, who had a present in the front seat of his car. The one-year-old has seven godparents in total of all whom have been invited.
The adorable little Prince's great-grandmother Queen Elizabeth II arrived just after 4pm. As expected, the Queen arrived solo, as the Duke of Edinburgh had previous engagements he had to attend. His uncle Prince Harry was also in attendance, along with Prince and Princess Michael of Kent.
Zara Tindall, one of George's godmothers, also arrived with her husband Mike Tindall and baby daughter Mia Tindall.
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Mia will be one of the few youngsters George's age at the party.
George's grandparents, Carole Middleton and Michael Middleton, arrived in separate cars, while his uncle, James Middleton arrived in a sports car, while George's auntie, Pippa Middleton, arrived later on her own.
William's former Nanny Jessie Webb was also seen arriving - Jessie helped William and Kate adjust to new life as parents in the months leading up to George's baptism - as well as George's godmother Emilia D'erlanger.
