Last week would have been her 55th birthday but a new documentary promises to show us a part of Princess Dianaโs we didnโt know much about.
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Princess Diana: Behind Closed Doors will reveal what Dianaโs life was like before she became a royal.
In a sneak peek of the documentary shown in the video below, Mary Robertson recalls hiring Diana as a nanny and talking about a trip the soon-to-be princess took to Balmoral castle, the royal familyโs Scottish getaway.
Robertson remembered asking the then-19-year-old if sheโd met Prince Andrew (Prince Charlesโ younger brother).
โโNo, it was actually Charles, but his mother invited me,โโ Robertson remembered Diana saying. โAnd I just burst out laughing at the thought of her referring to the Queen of England as a friendโs mother.โ

Princess Diana and Prince Charles
As Robertson tells it, Diana didnโt think much would come from that fateful meeting.
โI did say, โOh, my gosh. Do you think anythingโs going to develop?โ
โAnd very regretfully, you know, staring down at the floor, she said, โNo, I donโt think heโd look twice at me. After all, heโs 31 and Iโm only 19.โโ
โI said, โI wouldnโt be too sure,โโ Robertson said.
The documentary airs on Sunday 9pm (US ET time) on Reelz.
VIDEO: See a sneak peek of the documentary below