Queen Has ‘Sensitivity’ to What Prince Harry Is Going Through Because of Her Sister Princess Margaret

Although she publicly said she is “entirely supportive” of Prince Harry and Meghan Markle’s decision to leave royal life, privately the Queen – who puts duty before everything — would find such a choice unimaginable in her own life.

“The Queen will be very disappointed,” royal historian Robert Lacey tells PEOPLE. “Her job is to survive” — and to ensure that the monarch survives.

But this isn’t the first time she has encountered an unhappy royal spare – and it was her experience with her younger sister Princess Margaret that influenced her decision to let Harry set out on his own.

“She has a particular sensitivity to what Harry has been going through because of her closeness to Margaret and seeing the same dramas and tensions played out two generations ago,” says Lacey.

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View photos Princess Margaret and Prince Harry | Hulton Archive/Getty Images; EAMONN M. MCCORMACK/Getty Images More

Margaret struggled with her place in the shadow of her older sister.

“The younger-sibling syndrome is an enduring problem,” says Lacey. “The system has not found a way of giving them the recognition that they need.”

And as the older sibling has children, the problem only gets worse.

“Until Elizabeth produced heirs, Margaret was a possible future Queen,” adds Lacey. “It is a family situation of conflict that goes back over generations.”

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