He suddenly faces a future which is much less certain than seemed imaginable only a few weeks ago.
But the Prince of Wales, beset by concerns for the wellbeing of both his wife, Catherine, and, even more acutely, King Charles, has just received a timely boost to his morale.
It comes courtesy of the Earthshot Prize, initiated by William in 2019 and first awarded two years later when five winners, in separate categories, each received £1 million for devising solutions to what William described as 'some of the world's greatest environmental problems'.
At the time, Earthshot was administered by the Royal Foundation, established by Princes William and Harry back in 2009 to further their various charitable ambitions.
But in 2022 the prize was hived off, to be administered as an entirely separate charity.
If there were any doubts that it could flourish, they have now been conclusively banished.
I can reveal that the new charity — now called the Earthshot Prize — pulled in a mammoth £22.4 million in income in its first nine months alone.
While the Royal Foundation transferred £8.6 million, the remainder came from a variety of sources, as accounts just published by the Charity Commission disclose.
Donations totalled £7 million, while 'gifts in kind' accounted for just over £3 million, and a grant from the American Friends of the Royal Foundation for another £2.7 million.
The remaining five per cent – £1.1 million – came in sponsorship and from licensing income.
It's quite a contrast with the performance of the Archewell Foundation, established by Harry and Meghan after they resigned from their roles at the Royal Foundation.
Figures published by the U.S. tax authorities just before Christmas show that the couple saw donations plummet by £8.7 million, down from £10.3 million to just under £1.6 million in a single year.