Olive Baker attended St. Andrews University with the duke and duchess.
Emilia Jardine-Paterson attended Marlborough College with the duchess. She runs an interior design firm under her maiden name, Emilia d'Erlanger, and is said to be helping the couple decorate their home at Kensington Palace.
Earl Grosvenor (first name Hugh) is the son of the Duke of Westminster.
Jamie Lowther-Pinkerton served as private secretary to William and Kate from 2005 to 2012 and continues to work for the palace part-time.
The Honorable Julia Samuel was a close friend of William's mother, Lady Diana. She founded a nonprofit organization, Child Bereavement UK, which the duke supports.
Zara Tindall William's cousin, is married to former rugby pro Mike Tindall. The couple is expecting their first child around Christmas. Tindall is the only member of the royal family to be chosen as a godparent.
William Van Cutsem is one of William's oldest friends. His father, Hugh, who passed away in September, was a very close friend of Prince Charles.
More about the Royal Christening