Prince William, Harry reminded of Princess Diana's important lesson

Princess Diana, the world’s beloved humanitarian who dreamed of humanity thriving and blossoming, penned a life-changing and deeply personal letter to her sons Prince William and Prince Harry, sharing lessons that would shape their lives forever.

One week after her bombshell 1995 Panorama interview aired on the BBC, then Princess-of-Wales wrote an emotionally revealing letter to teach William, then 13, and Harry, then 11, the "importance of communicating on a deep level."

As reported by The Telegraph, in the letter which is set to go up for sale on September 9, the beautiful royal added she looked forward to "sharing my knowledge" with her sons, who were then 13 years old and 11 years old.

Following Harry and William's motehr's interview with Martin Bashir, Michael penned to her "that life would improve in time."

His upbeat message reportedly struck a chord with the princess as she  responded: "I returned from Argentina this morning to find your lovely letter awaiting me.

Diana wrote, "The content touched me deeply, as your words were profound + I was particularly able to relate to the point you made about self-knowledge + the price of moving on in life."

She added, "I hope the interview will support the many women out there who are, or have, gone through similar difficulties as myself. I look forward to the future where I will have the opportunity of sharing my knowledge.

She reportedly added, "It will teach William and Harry the importance of communicating."

She thanked Michael rom the bottom of her heart in concluding words o her letter.

The two-page letter, written on Kensington Palace stationary, was sold at auction in June for $7,243 (£5,330), but it has already returned to the market with the University Archives of Connecticut, according to the outlt.

The auctioneers called it one of the "best and most emotionally revealing" royal letters they'd ever seen.