Out of all decisions Queen Elizabeth II made over the past decades, only one wrong move stood out after it made Her Majesty struggle.

Within the 67 years of ruling the British monarchy, the current longest-reigning monarch also faced downs, too, which overshadowed everything she did well at.

From formerly being known as the "cold Queen" for keeping her distance from the public to almost getting shot by the royal guards after failing to ring them about his "midnight walk," Queen Elizabeth II surely got over those things already. However,  there is one thing she will always feel regret about.

Queen Elizabeth II's Biggest Mistake

In July 2017, Her Royal Highness allowed Charles, Prince of Wales and Andrew, Duke of York to remove her most trusted aide, Sir Christopher Geidt -- or Lord Geidt as what the royals called him before.

Lord Geidt, before leaving the palace, worked as Queen Elizabeth II's private secretary for 10 years and deputy private secretary prior to that. Most royal watchers thought that he deserved the position since he was known to be that staff who made the royal family members listen to him.

"While we never comment on the confidential employment details of individuals, it was previously announced in July that Sir Christopher Geidt is stepping down after 10 years as private secretary," the Royal Household said in a statement back then.

What the media called a "power struggle" came when Lord Geidt raised his concerns after Prince Charles unrolled his plans to gain a greater role before he becomes a King.

The Duke of York helped the heir-to-the-throne kick the Private Secretary out of the palace since "he shared a great dislike to him as much as Prince Charles did."

What made Prince Andrew shower him more with anger was the fact that Lord Geidt caused him to be removed from the U.K.'s trade envoy in 2011. The decision came after the royal family discovered his friendship with the late convicted sex trafficker Jeffrey Epstein for the first time.

Moreover, the private secretary also reportedly got "too much controlling" of Prince Andrew's expenditure.

What Happened After Lord Geidt's Departure

Royal watchers cannot do anything but wonder how much regret Queen Elizabeth II must felt for not doing a step in preventing her secretary from walking out of the office.

Since his exit, The Queen reportedly appeared weaker that she can no longer be firm enough to control her family.

The recent events proved that the 93-year-old monarch lacks something. From Prince Philip's accident to royal rifts, the Queen surely had enough headaches from the past year. Unfortunately for her, it does not stop there.

Recently, the members of the royal family -- particularly Princess Anne and Prince Edward -- voiced their concerns to the top advisor who replaced Lord Geidt, Edward Young.

A source from the Royal Household told The Times, "All the guns are blazing at Edward Young. He has not geared up the system to protect the monarch. Very senior members of the royal family think he should go."

The choice of Young as a replacement has came back to bite the Queen. Now, the Royal family members cannot do anything but to think of the "what ifs."

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