Uncle: Charles Had A Perfectly Normal Sex Life During His Bachelor Years 

Princess Diana, Prince Charles had quite the romantic life.

At the urging of his uncle, Lord Louis “Dickie” Mountbatten, who served as a father figure for Charles, he didn’t hold back when it came to women during his twenties.

“The advice that Dickie Mountbatten gave him was, ‘Have as many affairs as possible, he should sow his wild oats, and then find a sweet, charactered girl to put on a pedestal and marry her,’ ” royal biographer Sally Bedell Smith says in 

, a two-night television event from PEOPLE and ABC.

It wasn’t difficult for Charles to sow said wild oats. In fact, his uncle was vocal about it, telling members of the press: “Prince Charles has a perfectly normal sex life.”

But as the future king and an eligible bachelor, he had a number of girlfriends — including Diana’s sister, Sarah, and his current wife, Camilla (then Shand, later Parker-Bowles, and now, the Duchess of Cornwall).

“He was regarded as so dashing, so handsome,” Diana’s friend Lana Marks says of the young prince.

As his former girlfriend Jane Ward tells it, the navy man was seen as being daring and often leapt at the opportunities to pursue physical challenges.

“He was very much action man,” Ward says. “He loved to do rather daring things.”

RELATED VIDEO: Prince Charles Called His Marriage to Princess Diana a ‘Greek Tragedy’ in Letter to Nancy Reagan

One woman, however, stood above the rest: Camilla. They had a brief but passionate relationship in the early ’70s, that of course, picked up again in the ’80s, during his marriage to Diana.

“Camilla was to him, a safe haven,” Ward says. “Someone he could talk to.”

However dating the eligible bachelor came at a price: Endless photographer flashes, as well as press attention and intrusion.

“[It was] pretty intolerable,” Ward says. “It’s not easy for a girl to take all of that aboard. They broke into my house, left notes, followed me everywhere. It was definitely a deterrent.”

Life as the significant other of a prince had its pressures — and Diana learned that herself during her own brief courtship with Charles before their wedding. Of course, no one could have known then how intense the public scrutiny and media attention would be for Diana in later years.

For full PEOPLE coverage of the 20th anniversary of Princess Diana’s death:

•The Story of Diana, a two-part television event from PEOPLE and ABC, airs on ABC Aug. 9 and 10 at 9 p.m. E.T.

•Princess Diana: Behind the Headlines is streaming on the new People/Entertainment Weekly Network (PEN). Go to

PEOPLE.com/PEN, or download the PEN app on your favorite mobile or connected TV device

1 Mike Tindall Says Meghan Markle Will Do ‘Absolutely Fine’ as a Part of the Royal Family

When Queen Elizabeth Met Jackie Kennedy: The True Story of

3 Charles Spencer Says His Sister Princess Diana Would Have Been the ‘Best Grandmother Ever’ to Prince George and Princess Charlotte

Practicing for a Proposal? See Meghan Markle Play a Shrewd Fiancée on