During an unhappy childhood, Princess Diana's father slapped her mother, according to a new CNN documentary series.

"Diana," a six-part docuseries that begins on Sunday, follows the late British princess as she grew up in a turbulent family in rural England. The first episode, "The Girl from Norfolk," tells the story of Princess Diana's upbringing in the countryside.

CNN's Princess Diana documentary depicts Royal's childhood

Princess Diana did not grow up in a happy family, as she stated in recordings for Andrew Morton's book 'Diana: In Her Own Words,' which was included in the documentary.

One area of concern was Diana's mother, Frances Shand Kydd, and her husband, John Spencer, who wished for a son to continue the family tradition. According to Julie Montagu, an American-born viscountess featured in the docuseries, an aristocratic family appreciates Diana's practiced primogeniture, which is when the firstborn son inherits the family estate.

In the documentary, British journalist Bidisha Mamata said that as a wife, "You're supposed to keep popping out male children." Before becoming pregnant with a son, Princess Diana's mother gave birth to two girls, Sarah and Jane. John, the family's firstborn son, lasted barely a few hours before dying of lung disease, Business Insider reported.

Kydd gave birth to Princess Diana eighteen months later, after trying for another son and suffering the loss of a child her husband desperately desired, said the doctor. According to Montagu in the docuseries, Princess Diana grew up feeling as though she had already disappointed her parents since she wasn't the desired gender.

However, three years after Diana's arrival, Kydd and Spencer had their heir: Charles Spencer.

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Princess Diana's life before marrying Prince Charles

Princess Diana was recruited as a teenager to care after the son of an American businesswoman, who has now revealed what it was like to be a royal before marrying into the Firm. Mary Robertson hired Princess Diana, then 18 years old, to watch for her baby boy Patrik while they were away in 1980.

The businesswoman gave her first impression of the young princess in the new CNN documentary series 'Diana,' noting that the teen was different from the Princess the public grew to know.

Robertson claimed that Diana Spencer, the young Princess of Wales, was "shy" and had "no world experience" at the time. The future royal, on the other hand, was "absolutely amazing" with her child, according to the mother.

The mother stated that she had no clue the teen she had employed would be engaged to the Prince of Wales in the near future. Princess Diana and Prince Charles married in front of millions in St. Paul's Cathedral in London just over a year later, as per Express.co.

The future princess worked three days a week for the family, earning $5 an hour. But Princess Diana's job was not just one.

When she wasn't looking after Robertson's son, the youngster worked as a nursery school instructor. When Princess Diana moved to Buckingham Palace, she gave notice, but her mother said the two stayed in touch and were good friends.

How to watch?

Per Heavy, 'Diana,' a CNN miniseries airing Sunday, October 10 at 9 p.m. ET/PT, is the latest television or film to explore the life of Diana, Princess of Wales.

Sling TV's "Sling Orange" or "Sling Blue" bundles include a live stream of CNN and more than 30 additional TV channels. This option does not feature a free trial, but it is CNN's cheapest long-term streaming subscription, with the first month costing only $10.

You can watch 'Diana' live on your Apple TV, Chromecast, Xbox One, Samsung Smart TV, Roku, Roku TV, Amazon Fire TV or Fire Stick, LG Smart TV, Android TV, airTV Mini, Oculus, Portal, iPhone, Android phone, iPad, or Android tablet if you've signed up for Sling TV.

Alternatively, you may use the Sling TV website to watch on your computer. Sling TV comes with 50 hours of cloud DVR if you can't watch live.

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