King Charles’ ongoing cancer treatment has added a new level of urgency to the possibility of mending ties between him and Prince Harry — before time runs out. The two were briefly on the same continent in late May when the King and Queen Camilla visited Canada for the State Opening of Parliament — a trip widely seen as a gesture of support for the Commonwealth amidst growing strains with the U.S. However, despite their proximity, Charles and Harry did not meet.

While Prince William, 42, continues to keep his distance from the Duke and Duchess of Sussex, some royal commentators argue that it’s King Charles who should take the first step toward reconciliation with his younger son.

Still, within palace walls, uncertainty and reluctance remain.

There have been moments where reconciliation seemed possible, but according to royal biographer Sally Bedell Smith, “the underlying issue is trust.”

“King Charles and Prince William simply don’t feel they can trust Harry and Meghan with anything confidential,” she explains.

Sources also say the King isn’t being pushed by those around him to repair the relationship. Prince William hasn’t shown any interest in making peace, and senior advisers like Clive Alderton — who was criticized in Harry’s memoir Spare — aren’t likely to support any efforts at reconnection.

“There’s no one in his inner circle saying, ‘Be a good father and take the first step,’” says Valentine Low, author of the upcoming book Power and the Palace.

Even though Prince Harry publicly called for peace during a BBC interview after losing his legal battle over government-funded security on May 2, his remarks only seemed to deepen the divide. In the interview, Harry claimed the King “won’t speak to me because of this security stuff,” and added, “I don’t know how much longer my father has,” referencing the monarch’s cancer diagnosis.

“It may not have been meant as an attack,” Low notes, “but that’s how it came across — and it only makes it harder for Charles to reach out.”