Committed King Charles Working Far More Days Than Son William Despite Being on 'Last Legs' Amid Cancer Fight

King Charles has been hellbent on proving he's every bit the hard-working monarch that his mother, Queen Elizabeth II, was.

Meanwhile, Prince William worked fewer days than his cancer-stricken father, RadarOnline.com can reveal.

While Charles undertook official engagements on 118 days despite being diagnosed with what is believed to be pancreatic cancer, his son only worked on 71.

But palace insiders worry the 76-year-old royal may be working himself into an early grave.

While William, 42, understandably took time off after Princess Kate's cancer diagnosis, his downshift comes after he got a major pay raise, earning $30 million a year from the property portfolio he inherited from his grandmother.

Charles has long prided himself on being among the hardest-working royals – his main rival is his sister, Princess Anne.

William, however, has said he wants to have fewer engagements, focusing on ones that have a bigger impact – though critics said it's pretty much the same thing his father has always done.

The workaholic king ignored his doctors when they advised against the grueling tour of Australia and Samoa that left him looking exhausted.

An insider noted: "Charles wanted to show he's still able to fulfill his duties, but it was painfully obvious he wasn't well."