King Charles's health status remains uncertain as he continues to undergo cancer treatment.
Amid this situation, Prince William's role as heir apparent has never been more crucial.
The 76-year-old monarch has often spoken about the 'frightening experience' faced by cancer patients.
'The Crown will never felt closer to the Prince than it does now,' says royal commentator Katie Nicholl.
Charles' illness serves a clear reminder that William must begin preparing to take on the responsibilities as the next in line to the throne.
For context, Charles became monarch in 2022 at the age of 73, following the death of Queen Elizabeth.
However, just months later, the monarchy was shaken by the news of Charles being diagnosed with cancer.
He ascended the throne during a challenging period, becoming the oldest person in British monarchy to take the crown.
Despite the difficulties, Charles has remained optimistic about his health, notably during his four-day state visit to Italy in April, accompanied by Queen Camilla.
While planting a tree in Rome, Charles made a subtle reference to his own mortality, saying: 'Well, I do hope I shall live long enough to see a little bit of growth in the tree.'
Meanwhile, Prince William's royal responsibilities have increased in recent months-with Kate providing strong support to her husband at key events.