In what may highlight an emerging royal rift, Kate Middleton, the Duchess of Cambridge, reportedly showed her displeasure during the coronation of Queen Camilla, according to royal biographer Tom Bower. The Princess of Wales allegedly declined to curtsy to the new queen due to frustrations over the guest list.

Bower, who appeared on "Dan Wootton Tonight," asserted that both Middleton and her husband, Prince William, were dissatisfied with the coronation guest list restrictions. According to Bower, the princess could only extend invites to four family members, while Queen Camilla was able to have 20 attendees, including her own family.

On the show, Bower disclosed, "Camilla brought 20 Parker Bowleses to the coronation and there were four Middletons," noting that the Middletons' siblings' partners were excluded from the event. The biographer also suggested that those instrumental in improving Camilla's public image from being seen as King Charles' mistress to queen were surprisingly absent from the ceremony.

Bower also pointed out an interesting detail in the coronation footage, stating, "as the king and queen leave the thrones and head for the exit of Westminster Abbey, you'll see that everyone bows and curtsies to the king and no one moves a limb, a muscle, when Camilla passes."

He attributed this apparent omission of protocol to the lingering anger towards Camilla among the royal members. "All the people that helped Camilla get the crown on her head were excluded from that coronation, and they were furious," Bower stated, adding that this anger was evident among the congregation near the throne.

According to Bower, the ensuing tension was still evident at the following day's coronation concert at Windsor, where Prince William, in his speech, made no mention of Queen Camilla.

The royal biographer noted that the entire event had visibly fatigued Camilla, stating, "Those who met her in the weeks before the coronation noticed a very tired, very worn-out woman with telltale signs of age, and she's clearly exhausted by the whole thing."

This is not the first instance of alleged tension surrounding Queen Camilla. Royal expert Christopher Andersen recently claimed that she has been instrumental in further estranging Prince Harry from his father, King Charles, using the "no longer working royals" argument.

The Buckingham Palace and the Princess of Wales have yet to comment on these claims.