Prince George Alexander Louis of Cambridge was baptized into the Church of England Wednesday in a small private ceremony at St. James Palace.
The little prince, who turned 3 months old on Tuesday, showed off some impressively chubby cheeks.
"This is the first time he's been quiet all day," Prince William joked as he and Kate arrived at St. James Palace.
The ceremony, officiated by the Archbishop of Canterbury, took place in the palace's small Chapel Royal.
The royal family and the Middleton family were present for Prince George's special day.
The Duke and Duchess of Cambridge chose seven of their oldest friends to serve as godparents to Prince George:
Mr Oliver Baker (Oliver Baker attended the University of St Andrews with The Duke and Duchess)
Mrs David Jardine-Paterson (Emilia Jardine-Paterson attended Marlborough College with The Duchess)
Earl Grosvenor (Hugh) (Earl Grosvenor is the son of The Duke of Westminster)
Mr Jamie Lowther-Pinkerton (Jamie Lowther-Pinkerton served as Private Secretary to The Duke and Duchess of Cambridge and Prince Harry from 2005-2012 and continues to serve part-time as Principal Private Secretary and Equerry)
The Hon Mrs Michael Samuel (Julia Samuel was a close friend of The Princess of Wales)
Mrs Michael Tindall (Zara Tindall is The Duke of Cambridge's cousin)
Mr William van Cutsem (William van Cutsem is a childhood friend of The Duke of Cambridge)
The royal family's traditional Christening gown, worn by every royal infant born after 1841, was retired for preservation in 2008. Prince George wore a replica for the ceremony.
Ellie Hall is a reporter for BuzzFeed News and is based in Washington, DC.