Royal author Katie Nicholl recently wrote in Vanity Fair that the palace “did not have a game plan,” following the devastating dual cancer diagnoses for the king, 75, and his daughter-in-law, 42.

“This was not a public scandal or a crisis like an abdication,” Nicholl wrote. “Nevertheless, it forced a rethink for Charles in terms of his slimmed-down monarchy and how best to serve the people. The mighty House of Windsor, which not long ago had the world’s longest-reigning monarch at its helm, suddenly seemed very vulnerable.”

Andersen pointed out that both the king and his elder son William were in full support of a slimmed-down monarchy, one in which only a select group of senior royals would be fulfilling duties for the crown. But after Anne “joined the ranks of stricken senior royals,” it made the palace rethink the strategy.

Andersen believes all eyes are on William even more now as heir to the throne. As for Kate, everyone seems to be waiting with bated breath for her official return to public life.

“The simple truth is that the royal family cannot be whittled down to a precious few without the risk of having it grind to a halt altogether,” Andersen explained. “For over 70 years, the Windsors had longevity on their side – almost to a ridiculous extent. Queen Elizabeth II lived to be 96, and her husband Prince Philip was 99, the longest-living royal male in history.

“The Queen Mother was downing her favorite gin and Dubonnets right up until the end at the astounding age of 101. There seemed to be no need for redundancy, with senior royals seeming practically immortal and three generations of future monarchs … waiting in the wings.”

“It’s hard to blame palace officials for not having a plan in place to cope with the simultaneous cancer diagnoses of King Charles and Princess Kate, much less the sidelining of such a valuable supporting player as the Princess Royal,” Andersen continued. “The home team is running out of options.”

British broadcaster and photographer Helena Chard told Fox News Digital that once Kate is fully recovered and ready to go back to work, the public will feel more at ease about the monarchy’s future again.

“The enigmatic and elegant Princess of Wales is integral to the future of the monarchy,” she said. “Everyone is wishing her a full recovery. She just needs a few more months of cancer treatment and peace to get fully fit and well. When she is back to regular work, we will have forgotten about health battles and the fragile monarchy narrative.”

Royal expert Richard Fitzwilliams agreed.

“The Prince and Princess of Wales have been the future of the monarchy since their marriage,” he explained. “After them, their children … Kate has star power, beauty, poise and dedication. She and William have a very special cachet as a couple. She is championing studies in early childhood, and this is an important cause.

“Princess Anne’s accident this week shows what can happen, quite unexpectedly,” Fitzwilliams shared. “It was she who quite recently said a slimmed-down monarchy was impractical. It depends on what is wanted of the royal family.”

Several experts agreed not all royals possess the same star power as the Prince and Princess of Wales. Still, they’re considered the most desirable candidates to step in and help.

“Prince Edward and his wife Sophie are doing what they can to take up the slack,” said Andersen. “Princess Beatrice and Princess Eugenie could be asked to pitch in, which would be ironic given that Charles once contemplated stripping Andrew’s daughters of their titles as part of his plan to slim down the monarchy. Not surprisingly, Andrew angrily objected at the time.

“Still, none of these lesser royals have the star power to replace Kate if, for some reason, she is unavailable,” Andersen added. “Only Prince Harry, whose status in the polls ebbs and flows, might have the wattage to light things up again and keep the party going — if, somehow, he can work his way back into the king’s and William’s good graces. But that is a gargantuan if. For the time being, neither King Charles nor Prince William is willing to budge. The war between the brothers continues.”