London (CNN) -- The Duchess of Cambridge has successfully graduated as a "fully fledged member" of Britain's monarchy after fulfilling all her objectives one year on from her marriage to Prince William, a senior royal source has told CNN.
St. James's Palace, which represents her, William and his brother Harry, now regards Kate's "induction" as complete and the duchess herself feels "fulfilled" by the achievements of the past 12 months, the source said.
Confirmation of her smooth transition into the ranks of royalty will help dispel fears voiced ahead of last year's wedding that commoner-born Kate would struggle with the pressure of being thrust into the public eye.
But, thanks to guidance from her husband, Kate feels she has settled into her new life, CNN has learned.
"She would never judge her achievements but she has succeeded in doing what she set out to do in her first year," the source said. "She has achieved her objectives."
Kate's other mentor has been her father-in-law, Prince Charles, with whom she has become close. "They spend a lot of time together. They go on visits to the opera and art galleries. They share passions that neither of the princes share. They get on very well."
The source was speaking to CNN for a new documentary: The Royals; Kate, Duchess of Cambridge airing on May 4. In it, CNN explores how the whole royal family has thrown its support behind their newest member as she finds her feet.
"The queen has made a lot of time for the duchess. [Kate] gets on very well with the queen. They have a warm relationship as was evidenced in Leicester," says the source, referring to a visit last March when the pair were seen chatting and smiling.
It has been a whirlwind year for Kate. Her wedding last April, one the biggest media events in history, was followed by a triumphant tour of Canada, which she regards as the highlight of her official year, and a trip to the United States.
When the duchess returned to Britain, she began shaping her own identity within the royal family.
In January, she announced her support for four charities and began her first solo engagements. Last month she made her inaugural speech with the help of William who, CNN has learned, coached her via phone from the Falklands where he was on military service.
By delivering her first speech, Kate completed the full range of official duties expected of a working royal.
A small palace team has provided what training it can for the duchess, but they accept that the best insight comes from William and Charles.
However, Kate has also proved to be a natural.
"For her, the public engagements are a joy," the royal source said. "She enjoys it. Not much fazes her. She is confident enough to handle it. She is strong-willed. She knows her mind. She is professional."
Kate's hands-on approach came to light when the media was bombarding the palace with calls demanding to know the name of her new puppy.
The duchess was unwilling to let her puppy become a public relations event, CNN understands. Instead she revealed it naturally during a visit to a school when a student asked her.
In case you missed it, the newest member of the royal family is called Lupo.