Prince William and Princess Kate are reportedly feeling “intense anxiety” about the prospect of ascending to the throne, a Royal insider has claimed. The Duke and Duchess of Cambridge are said to be apprehensive as they face the possibility of taking on the roles of King and Queen Consort sooner than expected.

The King was diagnosed with cancer in January, and his treatment continues, leaving the Royal Family stretched thin. William, 41, is next in line for the throne and will be supported by Kate, aged 42, in fulfilling Royal duties and attending engagements.

This looming responsibility is allegedly causing the couple considerable stress. In her commentary, former Vanity Fair editor Tina Brown noted: “News of Charles’s cancer has put William and Catherine in frightening proximity to ascending the throne … The prospect of it, I am told, is causing them intense anxiety.”

A well-wisher at St George’s Chapel commented: “I think it’s really significant (Charles’ attendance). It indicates that he’s doing good and that he’s definitely on the incline in relation to his health, so that’s really nice to see. I also would like to thank him for attending the service today because I know that must’ve been a lot, but he shows himself to be committed to this nation and to people all around the world.”, reports the Mirror.

The 75-year-old monarch greeted and conversed with those who had gathered at the castle in a surprise walkabout after the service on Easter Sunday. However, he continues to receive treatment for his cancer, and concerns persist.

“Some believe, however, that if Charles and Kate were to be permanently side-lined, forced into greatly reduced roles for the longer term by ongoing health challenges, a Prince William regency would look desperately short-handed. Officials are as busy as ever. There is no question of decisions being taken by anyone other than the king,” said Tom Sykes, Royal correspondent with Daily Beast.

In February, His Majesty did not immediately specify which type of cancer it is. The statement read: “During The King’s recent hospital procedure for benign prostate enlargement, a separate issue of concern was noted. Subsequent diagnostic tests have identified a form of cancer.”

Both Kensington Palace and Buckingham Palace have been contacted by the Mirror for a response.