Princess Anne petrified Camilla to the core after she married Prince Charles

Princess Anne sent chills down Camilla Parker's spine after she joined the royal family officially.

The Queen's only daughter intimidated Camilla for years, after she tied the knot to Prince Charles.

According to royal author Penny Junor, Anne's chilly conduct was extremely nerve-racking for Camilla, mainly because they loved the same person, Andrew Parker Bowles.

"The affair between Andrew and Anne came to nothing but I think they were hugely fond of each other. And they remain hugely fond of each other. And I think Camilla has always had a bit of a problem with that, partly because of the affair," Junor told Channel 5.

"But Princess Anne is quite a tricky character and she can be quite abrasive Over the years, Camilla has been slightly intimidated by her," she added.

Junor said Anne's fling with Andrew led her to meet future husband, Charles, "It was while he was having a relationship with Princess Anne, that Camilla was introduced to Prince Charles and had a little fling with him.

"I guess there was an element of tit-for-tat in Camilla's relationship with Charles. There was the man she loved having a fling with Princess Anne. What's sauce for the goose, sauce for the gander," Junor continued.