The young future princess looks every bit the English schoolgirl in the rarely seen photo

By Erin Hill and Simon Perry
Updated August 20, 2015 12:15 PM
Credit: Alban Donohoe

No awkward phase here!

It’s hard to imagine Princess Diana as a gawky adolescent. And a rarely seen picture of the future royal as a young girl proves she sailed through her teenage years with the same classic style and grace she exhibited as the Princess of Wales.

In this #TBT photo from 1975, Diana, who was around 13 years old at the time, is seen alongside her father, Charles Spencer, and siblings, Lady Sarah Spencer, Earl Spencer and Lady Jane Spencer.

Dressed in a pleated skit and sporting side-swept bangs, Diana looks every bit the English schoolgirl in the photo, which was taken in front of a window in the family’s new home at Althorp.

Born at Park House on Queen Elizabeth‘s Sandringham country estate, Diana spent most of her childhood there. And the girl who would become the world’s most famous royal so loved the house that she and her siblings said goodbye to every room in the 10-bedroom mansion when they left for Althorp in 1975, her biographer Andrew Morton has written.

The children were largely brought up by their father and his second wife, Raine, following his divorce from Diana’s mother, Frances.

Longtime chronicler of the royal family Judy Wade, tells PEOPLE Diana’s father did his best to create a happy childhood post-divorce. He even secured a camel to be a star attraction at a birthday party one year.

“Diana was very close to her brother, Charles, as they were at home together when the older girls were away at boarding school,” Wade says. “Charles was the boy – and heir – they had longed for.”

Lady Jane wed Sir Robert Fellowes, who became Queen Elizabeth’s closest aide, her private secretary during the years of Charles and Diana’s estrangement and divorce, while Lady Sarah, who dated Prince Charles briefly ahead of Diana, was her younger sister’s lady-in-waiting on some foreign tours.

Donald Trump Hoped Princess Diana Would Be His ‘Trophy Wife,’ Says British TV Anchor

After her tragic death in 1997, Diana was buried at Althorp, which is located in Northamptonshire. Her grave and memorial are on an island in the lake within the large estate.

Today, the beloved princess’s legacy thrives thanks in large part to her sons, Prince William and Prince Harry. Proud parents Will and Princess Kate even chose to name Princess Charlotte after her late grandmother.

Want to keep up with the latest royals coverage? Click here to subscribe to the Royals Newsletter.