Trained at the famous Norland College, she will be joining George and his parents on their upcoming tour of New Zealand and Australia, and the couple is "delighted she has chosen to join them," a palace source says.
It first emerged 10 days ago that the Duke and Duchess of Cambridge had taken on a Spanish woman for their household – an experienced nanny, in her 30s, "totally dedicated to the family" she was working with.
Borrallo is "living in" with the family at Apartment 1A at Kensington Palace, PEOPLE has confirmed. This is very much in keeping with what would be expected by Norland nanny experts.
Claire Burgess, a fully trained Norland nanny who now works to help train other nannies, told PEOPLE that the couple would have been looking for someone who was comfortable working in their home. "Someone they can trust and can look after their baby to the best of their ability," she says.
The couple had tried to keep the number of staffers relatively small, and Borrallo joins a team that also includes a housekeeper and a driver/orderly. Burgess says the couple would want "to keep the number of people coming and going from the home to a minimum, so I think they would have most likely have one person doing the majority of the care."
In the early days post-birth, Kate mainly had help from her mother, Carole, back at the family home in Bucklebury. But, by the end of the summer, they had enlisted one of William's former nannies, Jessie Webb, 71. That was always likely to be a temporary measure, and the tour of New Zealand and Australia provided the perfect time to get someone new, and long term, on board.
"They are being sensible in trying to keep it as personal as possible. And hopefully they will be able to enjoy their baby away from the media and experience parenthood," Burgess adds.
A Norland College spokeswoman would not say when Borallo was at the famous institution, but she noted: "We want to wish her all the best for her new position."