Ken Wharfe – who protected Princess Diana and her two sons from 1987 until 1993 – believes that Prince Harry should have done more to shield his father-in-law.
The 69-year-old revealed, "He's not an unintelligent guy. He's been through the mill himself, he knows what press intrusion is like.
"He has a drawbridge and a portcullis to hide behind when they pursue him. Thomas Markle doesn't."
Thomas no longer speaks to his daughter and the Royal family has distanced themselves from the former Hollywood lighting man.
The former bodyguard added, "I don't think we should dismiss her father, as someone who made mistakes here, as an ogre. His behavior is a result of poor advice or no advice."
And he believes that the Royal Family should have known about the problems even before Harry and Meghan got engaged last December.
He explained that Meghan's family were "ordinary folk, divorced, living in a foreign land and suddenly their daughter's marrying a prince."
Wharfe – who watched Prince Harry make plenty of mistakes in his own personal life – believes the whole situation was badly handled.
He recalled Harry bringing negative publicity on both his family and himself after he was photographed wearing a Nazi uniform in 2005 and when he was snapped playing naked billiards in a Las Vegas hotel room in 2012.
The trusted bodyguard was left devastated when Princess Diana died in a Paris car crash in 1997 aged only 36.
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