But as I’ve previously written, Harris, 60, should run only if deep down she wants to solve California’s festering problems — with wildfire prevention high on the list.

“Things fester or we end up doing things that are hurtful to us.”

He said this interaction "festered in your mind from that moment onwards and that was enough to trigger an attempt to cause really serious bodily harm - as an act effectively of revenge".

This zinging back-and-forth is also in evidence in the film, in which these sisters metaphorically tear each other apart and then try to heal the wounds that have festered.

McCartney said confusion over the break-up had festered because the band's new manager Allen Klein - with whom he refused to align - said he had needed time to tie up some financial loose ends.