"I was told that the Palace had advised Kate to watch footage of Princess Diana getting in and out of her car so that she could learn how to handle the paparazzi," royal expert Katie Nicholl wrote.
"Kate told a friend it was 'creepy' watching the archival footage, but it seemed to work."
Ms Nicholl added: "Whenever she was photographed leaving her Chelsea home of the Boujis nightclub, Kate excited her car gracefully, smiled broadly, and navigated the paparazzi-lined pavements with aplomb."
Meanwhile, Editor-in-chief of Majesty magazine, Ingrid Seward says Diana would have adored Kate.
"I think she would have been very fond of Kate, because Kate does everything right and looks gorgeous," she told the Daily Mail.
WATCH: Prince Harry speaks about his mother: 'Every Time I See a Camera, It Takes Me Back'
"And I think she would have recognised how good Kate is for William, because William is emotional and difficult."
Diana was killed in a car accident in Paris in August 1997.
Prince William previously opened up about his mothers relationship with the paparazzi, telling a HBO documentary she would often cry.
"If you are the Princess of Wales and you're a mother, I don't believe being chased by 30 guys on a motorbike who block your path, who spit at you, who shout at you and who react really badly to get a reaction from you, and make a woman cry in public to get the photographs, I don't believe that is appropriate," he said.
"I sadly remember most of the time that she ever cried about anything was to do with press intrusion."
