Dyer had left royal service by then but his legacy and his loyalty continued even as he forged a career in hospitality. Personable and astute, in 2009 he successfully established and ran a chain of pubs, before selling them just eight years later for more than £10 million ($19.3 million). Prince Harry was an usher at his wedding in 2010, a compliment returned when he wed Meghan at Windsor Castle in 2018.

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His son Jasper, who served as a page boy, is Prince Harry’s godson. Dyer became godfather to the couple’s son, Archie, born in 2019. Their closeness is not in dispute.

Yet interestingly, following the couple’s departure, as shocked courtiers, dismayed friends and heavy-hearted family quietly aligned themselves with Team Sussex or Team Wales (formerly Team Cambridge), Dyer’s strong links with Harry have not rendered him persona non grata.

While he may not speak to William directly, it is understood he is something of a conduit through which Harry stays in touch with family members and friends in the UK.

“As a former equerry, Dyer understands the way royal life works and that is important,” says one unnamed insider. “Before, Kate would have acted as peacemaker but she’s now incapacitated, and having been on the receiving end of one too many Sussex salvos she is understandably less inclined to broker a rapprochement.”

It is Dyer’s straight-bat reputation that puts him in a pivotal position post-Megxit – a term that increasingly thin-skinned Harry regards as slur, rather than a jolly portmanteau.

If only he had consulted Marko about this and so much else; like the optics of a filial visit that appeared so perfunctory it was over before it had begun. But he clearly did not.

In his incendiary 2023 memoir Spare, Harry wrote fondly of his role model: “Of all Pa’s people there was consensus that Marko was the best. The roughest, the toughest, the most dashing.”

He went on to recount the time when his father dispatched Dyer to grill him at boarding school to “find out the truth” about whether he had been taking drugs. Charles instinctively knew he was not the right person to tackle such a sensitive issue. His worldly equerry took it in his stride.

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Then, when his younger son fessed up to smoking cannabis, his father arranged for the shamefaced prince to spend a day at a residential centre for drug users in south London – accompanied by, who else? Marko.

Small wonder they stayed chums. Fast forward to 2022 and Dyer was diagnosed with stomach cancer. After enduring a gruelling 14-hour operation he remained in hospital for six weeks before being discharged.

Last year his niece, the classical soprano Alicia Lowes, told reporters that her uncle had “turned the corner and is cancer-free”.

Against this background, Dyer can provide a valuable – if immensely hard-won – insight into the emotional turmoil that the spectre of cancer brings.

A friend, a father, a survivor and a confidant, he alone can give Harry the perspective – the wake-up call – that he will need in the weeks and months to come as his father’s cancer treatment continues.

The Telegraph, London

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