Seeing the royal hack pack in full cry on Monday reminded me of the week I spent with the late James Whitaker, the Daily Mirror’s chief royal correspondent. This was for a profile I was writing about him in a colour supplement in 1993. It was a memorable experience, not least because of the message he left on my answering machine the day the piece came out.

‘I know I said I didn’t care what you wrote, but you could have at least got your fucking facts right,’ he said. He then started listing the facts I’d got wrong: ‘Number one, the Princess of Wales did not call me “the big fat tomato”. It was “the big red tomato”. Number two…’ He was still going strong by the time the tape ran out.

The complaint was ironic, coming from a royal correspondent. After a week with Whitaker — who called himself ‘the man who really knows the royals’ — I’d concluded that he and his colleagues made up most of their stories out of whole cloth.

The peg for the piece was the publication of his book Diana vs Charles: Royal Blood Feud. His central claim — ‘scoop’ is too generous a word — was that MI5 had bugged the royal couple, a story that was subsequently denied by the Home Secretary, denied by the security services and denied by Buckingham Palace. Indeed, it turned out that Charles and Diana had been together at Highgrove on the day the bugged telephone conversation was supposed to have taken place. During one particularly gruelling cross-examination on LBC, Whitaker was forced to admit to Andrew Neil that his ‘source’ for the story was not an employee of GCHQ but Dave Alford, a royal hack on the People.

Another of his claims was that the reason Charles found Camilla so irresistible was because of her poor personal hygiene. I sat opposite him in a New York television studio while he relayed this information with a straight face.

‘She has an animal magnetism that really turns him on,’ he said. ‘As you’ll see in the book, she’s not the cleanest of women, she doesn’t wash all that often… that really turns him on.’

Now, I suppose it’s possible that might be true, just improbable. When pressed, he said he had it from an ‘unimpeachable source’, but I doubt he’d even spoken to a disgruntled footman. It sounded like something he’d invented to please the American public, whom he judged to be pro-Diana and anti-Camilla.

The high point of the week was a visit to London Television Centre. He’d just finished recording an interview with Clive Anderson when he discovered that the Queen Mother had been admitted to hospital. He was due to fly to New York on Concorde the following morning and was filled with horror at the thought that he’d have to cancel his American book tour. ‘I don’t need that, do I?’ he said. ‘I do not need the baked bean going.’

To avoid any delay, he decided to record an interview with GMTV that could be broadcast in the event of her dying. ‘It’s just a devastating blow to the royal family,’ he said, doing his best to look sombre.

‘She was 92 and three quarters and you’re very fragile at that age. I always felt she was one of those ladies who was going to go on and on and then go very fast and that’s the way she’s gone.’

I suppose there’s no difference between this and a newspaper preparing a memorial supplement to a still living public figure, but it felt more dishonest somehow. Whitaker must have sensed this because he turned to me immediately afterwards and said, ‘You can’t fucking use that.’ I reasoned that since he hadn’t told me it was off the record beforehand it was fair game.

I don’t mean to imply by any of this that I disliked Whitaker — or even disapproved of him. On the contrary, I thought he was an immensely entertaining figure and if he did give his stories a bit of ‘topspin’ — his phrase — I don’t suppose his relationship with the truth was any more semi-detached than that of his colleagues. Royal correspondents, like humour columnists, have a licence to embellish, and readers know the deal.

In the ongoing soap opera that is the story of our royal family, they’re the scriptwriters. Whitaker passed away last year, but, thanks to the royal baby who was born on Monday afternoon, his ilk will continue to play a part in our national life for at least another 90 years. Long may they reign.