EXCLUSIVE: Prince William 'Urged to Undergo Anger Management Therapy' Ahead of Taking Throne Over Fears He Will Fail to be 'Diplomatic'

Prince William is said to be being urged by royal insiders to control his fiery temper before becoming king amid fears his explosive outbursts could undermine the diplomatic restraint expected of a future monarch, RadarOnline.com can reveal.

The 43-year-old Prince of Wales has long cultivated a calm public image, but fresh claims from royal author Christopher Andersen suggest tensions behind palace walls can become intensely heated.

In his new book, Kate! The Courage, Grace, and Power of the Woman Who Will be Queen, Andersen alleges William's temper has at times alarmed even his cancer-battling father, King Charles, 77.

Royal sources have also told us concerns have quietly grown over whether William's confrontational instincts could become problematic once he ascends the throne.

One insider said: "There is anxiety in some royal circles that William can become intensely emotional and reactive when frustrated. The monarchy depends heavily on diplomacy, patience and self-control, and people around him know those qualities will be tested even more once he is king."

A palace aide added: "William is deeply passionate and protective, but that intensity can sometimes spill over into anger behind closed doors."

Andersen has described William as capable of intimidating eruptions despite his polished public demeanor.

He said: "William is capable of great bellowing tantrums."

In his book, Andersen wrote the prince is generally respectful toward palace staff and strangers and never directs his temper toward his wife, Catherine, Princess of Wales, 44, or their children, Prince George, 12, Princess Charlotte, 11, and Prince Louis, eight.

However, the author claimed William has repeatedly raised his voice during arguments with Charles.

A former Highgrove staff member quoted in the book said "when he gets frustrated, (William) does resort to shouting" at the king.

The staffer added: "William has a huge, booming voice. Much louder than his father's, so it's not something you soon forget."

Sources familiar with palace dynamics said William's frustration often stems from pressure surrounding royal duty, public scrutiny and long-running family tensions, particularly involving his long-estranged brother Prince Harry, 41.

One royal insider added: "William feels an enormous weight of responsibility and sometimes that pressure manifests itself emotionally. There have been moments where advisers felt he needed help managing stress and channeling his anger more constructively, and have advised that he should attend anger management therapy."

Harry previously detailed one alleged confrontation with William in his memoir Spare, in which he accused his older brother of physically attacking him during an argument over his wife Meghan, Duchess of Sussex, 44.

Harry wrote William, who was apparently "piping hot," grabbed him by the collar and knocked him to the floor, leaving him injured after landing on a dog bowl.

Andersen argued the prince's temper may partly reflect behavior learned within the royal household itself, describing Charles as similarly volatile in private.

He said Charles "has a Vesuvius temper."

The author previously claimed in another royal biography Charles once tore a sink from a wall after losing a cufflink down a drain in a fit of rage.

The king also drew public attention following Queen Elizabeth II's death in 2022 when cameras captured him angrily reacting to a leaking pen during an official signing ceremony.

At the time, a deeply grieving Charles could be heard saying: "Can't bear this bloody thing.

"Every stinking time."