Although Queen Elizabeth II is the most-loved monarch in the world, she is not perfect -- far from it. In fact, Her Majesty  has faced a major controversy that she considers her "greatest mistake."

As the current longest-reigning monarch, Queen Elizabeth II has experiences all kinds of ups and downs that strengthened her through the years. However, a major disaster years ago ignited several controversies that truly tested her.

The Queen's Greatest Regret

In 1966, Aberfan, South Wales village experienced a catastrophic mining disaster that claimed the lives of over 100 children.

As the head of the state, people expected the Queen to visit the village. However, she refused to come since her presence would distract the search and rescue operation.

But years later, Queen Elizabeth II confessed that it became one of her greatest regrets. Her Majesty said that she wished she had visited the village sooner to offer her support and sympathy.

Meanwhile, royal commentators sat down and tackled the topic in Channel 5's latest royal documentary titled "The Queen: In Her Own Words."

"The Queen did say this to her private secretary, Martin Charteris," royal expert Ingrid Seward said. "She said, 'I feel one of the biggest mistakes of my reign was not getting to Aberfan sooner'."

Meanwhile, other royal experts discussed how the event left an impact on the Queen, as it marked the moment when Her Majesty realized that she could have comforted the public even through her words.

"The Queen realised that people did want to see her. The Queen could do something that was very important and rather special," Royal biographer Hugo Vickers uttered. "This was something that other people couldn't do. It is really the ultimate kind of respect that can be made to that community."

Eight days after the incident took place, the Queen finally paid a visit to the village and spoke with the locals.

One of the rescuers, Sir Mansel Aylward, recalled how Queen Elizabeth II's face changed as if she was going to cry. He claimed that after a few seconds, the monarch let her guard down and wiped "one or two tears" that came down.

Another Mistake Made By Queen Elizabeth II

It is worth noting that the Queen pledged to serve the monarchy until she dies. As she continuously serves the monarchy, she has had a fair share of regrets that somehow causes her anxiety until now.

In July 2017, Her Royal Highness allowed Prince Charles and Prince Andrew 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 a deputy private secretary before 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 about Prince Charles' plans to gain a greater role before he becomes King.

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

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