Confessions of the Queen's Vicar: Diana's 'terrible' upbringing, Andrew on the rampage and Princess Margaret's VERY distracting decolletage... an indiscreet portrait of the off-duty Royals

It is one of most exclusive invitations possible: an offer to spend the weekend with the Queen at Balmoral.

And for the Reverend Jack Kellet, it proved a quite extraordinary experience – a glimpse into the Royal Household at an exceptional period in its history.

It was 1981, and Prince Charles had just married a young and shy Diana.

Today, in intimate and at times hilariously indiscreet detail, the 86-year-old minister paints an affectionate portrait of the Windsors at their most unguarded: joking, chatting, even bickering among themselves.

He also shines a light on the surprises and unexpected pitfalls of being a Royal guest: being teased by a Prince about his sermon, committing the ultimate faux-pas – stepping on one of the Queen's corgis – and being warned by a valet to expect dirty jokes…

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The Reverend Jack Kellet got a glimpse into the Royal Household at an exceptional period in its history when he was offered the chance to spend the weekend with the Queen at Balmoral

A-A-D-A-A-M!' the Queen shouted into the great east doorway of Balmoral Castle, trying to attract the attention of her equerry, Squadron Leader Adam Wise. 'Adam!'

Yes, it was the Queen, believe it or not, her hands cupped around her mouth to make sure her shout would go right through the reception hall. Queen Elizabeth II – so relaxed, natural and responsive.

The year was 1981. Prince Charles and his bride Diana had arrived home from honeymoon a few days earlier, and I had been invited to be a guest of Her Majesty for the weekend and preach at Crathie Church on the Sunday morning.

I arrived at 6.30pm on the Friday and a policeman told me to drive up to the castle where Adam would be waiting for me.

A letter from the Queen's chaplain at Crathie had told me I would not meet the Queen until just before dinner at 8pm – when I should remember to say 'Your Majesty' while giving a gracious nod of my head, and then be careful to say 'Ma'am' whenever the Queen chose to speak to me thereafter. But when I drew up, no one was there.

I recalled a previous chaplain had his bag removed from the boot of his car by a valet, and that the next morning the valet reported to him before breakfast with the old raincoat the minister also kept in the boot – for crawling under his old banger to find out what was wrong – beautifully cleaned, pressed and folded in white tissue paper.

I got out of my old car and had just started to lift out my bag when I was startled by the sound of dogs scurrying out of the castle. And then I saw the Queen in a headscarf striding out on the heels of the six corgis. She gave me a smile and a wave. I felt quite nonplussed.

A letter from the Queen's chaplain at Crathie had told me I would not meet the Queen until just before dinner at 8pm – when I should remember to say 'Your Majesty' while giving a gracious nod of my head

The Queen, having passed me, suddenly turned on her heels and strode towards me with her right hand outstretched and a most lovely smile taking over her face. 'I'm sorry,' the Queen said, beaming in welcome. 'I thought I recognised you as one of my staff, and then realised you must be our minister for the weekend. Is no one here to see to you?'

The next moment she was running up to the porch – and I mean running: 'A-A-D-A-A-M! A-DAM!'

There was just one 'little thing more' from the equerry on my first briefing. The question was: how was I with dirty jokes? I am sure the Queen herself would have been horrified. But I later realised that no doubt this check was required by others in the castle.

An amazing grace

When my valet had shown me to my room, he unpacked my weekend bag and said: 'Dinner is at 8 o'clock, sir, and I will be back to take you down to the drawing room at 7 o'clock.'

Then, turning in the doorway, he said: 'It may be, sir, that the Queen will ask you to say grace. Would you be prepared to do this, please?' When I said this would be a great privilege, the valet paused and, gazing at my face more intensely, added: 'I hope you won't mind, sir, but I've been told to ask you if the grace is likely to be long or short.'

On hearing that the grace would be short, the relief on the valet's face was obvious and, much more relaxed, he confided: 'Oh, Prince Andrew will be so pleased.' He revealed that when they had the Moderator [Scotland's most senior church minister] the previous week, the grace was so long they thought it was the sermon!

Reverend Kellet recalls how Prince Charles and his bride Diana had just arrived home from honeymoon

Later, on the Sunday evening, the moment I walked into the drawing room for dinner, Andrew called out to me from the company around the fireplace: 'Congratulations, minister!'

'What's that for?' I asked.

'Fifteen minutes and 32 seconds! The length of your sermon!'

'Mmm, how do you know that?'

'I put my stopwatch on you!'

Some years later, an older minister who had been at Balmoral told me that no sooner had he opened grace with 'Oh gracious God, we thank you for this food' than the Duke of Edinburgh had said 'Amen', and that was that…

DJ's mango surprise 

Adam told me that at dinner I would find myself placed to the right of the Queen. He said she usually talked to the person on one side for the first half of the meal and turned to her other neighbour for the second half.

This proved not to be the behaviour of the warm, gracious and friendly personality who came up to me in the reception room before dinner and then resumed the conversation at the table the moment after I had said grace.

We sat around a long, oval polished wooden dining table. When we had started on our main course, I asked her if it was venison we were eating – my wife was a home economist and would want to hear about the food. 'It's roe deer,' she replied. 'Better.' And then she passed me the menu – which only she had – and asked if I'd like to take it home for my wife.

As our plates were being taken away, I said it had been distressing to see on TV the recent frightening incident during Trooping the Colour, when a man in the crowd produced a pistol. The Queen's reply showed her real security worry was for her daughter Anne and the previous occasion when a man managed to get into Anne's car and seriously wounded her driver.

When I saw the pudding before me, the Queen explained that we were having a Swedish recipe for redcurrants. And then she asked if I had ever ventured upstream to Dubh Loch. 

'One day I was walking on the high path along the hillside, talking with Prime Minister Mr Heath, and no one else there except my man some way behind, when a little yellow plane suddenly appeared overhead. That was a fright. Mr Heath's face turned as red as that,' she said, pointing to my pudding. 'It turned out to have been American tourists wanting a look!'

Our meal complete, the Queen said there was now a surprise from Charles and Diana: a member of staff appeared with a basket of mangos. Charles explained that as he and Diana were waiting in Cairo airport, they saw a military vehicle driven at speed on to the tarmac. 

The soldiers on guard responded instantly to this unexpected danger, but the president beamed in pleasure and relief: here was a crate of mangos as a parting present.

A bump in the night 

In the breakfast room the next morning, Prince Andrew left his table companions to speak to me. 'Minister, I want to apologise to you. We must have disturbed you when we were horsing about along the corridors during the night and somehow managed to bump into your door. I'm sorry.'

Andrew and his brother Edward had some teenage friends staying and it had been no surprise there had been running about and squealing during the night.

Indiscreet Margaret 

When I slipped into the drawing room at 7 o'clock that evening, Princess Margaret was quizzing the others about when they had first been informed of the date of Charles's wedding to Diana because she felt she ought to have been one of the first to know and was not.

When she noticed the minister for the weekend had come into the room, she rose immediately and walked across to me. I had sat down on the nearest seat to the door, an old nursing chair, upholstered in Royal Stewart tartan.

The next evening the Princess explained she had come over instantly as no one used this chair; it was the one Queen Victoria sat on, next to the window as she suffered from 'hot flushes'.

Reverend Jack Kellet recalled how Princess Margaret (pictured) wore an 'extremely low' cut white dress

There was no way I could have been discomfited by this disclosure. But I did find myself embarrassed by the presence of the Princess in front of me. She stood too close. Because she was a small woman, I had to look down to her face as we spoke and her white dress was cut extremely low. Her breasts, brown from the Mustique sun, were very prominent.

It crossed my mind that this lady's governess, and her exceptionally occasion-conscious mother, must have told her how to behave in such circumstances. And then I noticed in the background Charles and Diana slipping quietly from another door through the drawing room and into an annexe. Diana appeared much taller than I had imagined – disturbingly so. She seemed to be stooping slightly, as if over-conscious of her height.

I took the chance to tell Margaret that my wife and I had enjoyed the televised marriage service. 'The cameramen focused on me when I was looking very sad, as if I disapproved of it all, when the truth is that this was during the hymn I Vow To Thee, My Country, which always moves me deeply,' she said.

When I replied that Diana had chosen that hymn, Margaret said she hadn't known this, and added: 'That girl has had a terrible upbringing and the Queen is hoping she will make us her family.'

A sore point 

Sunday dinner over, I returned to the drawing room. After a few minutes, the Queen left, but a few minutes later she was back and exclaimed to everyone: 'What do you think of that? She's too busy to take a call from me.' I ventured to seek confirmation of this surprise. 'Am I right that the Queen and Head of the Commonwealth has been prevented from contacting her mother?'

'That's it,' the Queen replied. 'I'm worried about the Queen Mother because she has a very sore leg, and when I phone up to the Castle of Mey, I'm told she is holding a cocktail party and is not to be disturbed. Sore leg and holding a cocktail party!' Smiles all round.

Crathie Kirk near Balmoral, Aberdeenshire, Scotland, where the Queen often enjoys taking walks

Charles said he also encounters problems: 'I'm told I'm being put through but then she presses the wrong button and cuts me off.'

Some years later Keith Angus, the minister at Crathie, was succeeded by Robert Sloan. I was told the Queen Mother, who joined public worship in Crathie every Sunday when staying at her estate next to Balmoral, was furious when the new minister replaced the King James Bibles with a modern translation, and she let the Kirk Session know.

The next week, the Queen Mum instructed her chauffeur to find out what Bible was to be used before she entered. When he returned with the bad news, she told him to drive her home.

Corgi calamity 

On the Sunday when we had finished lunch in the garden and the Queen rose to go, I stood up too, and then stepped back from the table to let Her Majesty return to the castle.

'E-e-k!' I realised with horror I'd stood on the foot of one of the corgis. The Queen just gave me that smile again. Later that evening, I asked Charles how he had got round to asking the Queen for permission to marry Diana. He said he'd caught her in a corridor when she stopped by a radiator to feed her corgis.

The vicar made the mistake of stepping on one of the Queen's beloved corgis (with whom she is pictured)

Undercover queen 

One of my final engagements with the equerry came just after Sunday lunch. Walking cross country back to the castle, we met the Queen out for a walk all by herself and looking supremely relaxed.

Standing in the sunshine, we had a long chat. I said I had been brought up close to Holyrood Palace and it was rumoured the two Princesses – Elizabeth and Margaret – often walked in King's Park. 'Yes, we did,' the Queen said. 'I still do.'

'Surely you are recognised now?'

'Oh no. I like to walk whenever I get the opportunity. One summer, sailing up here through the islands, I went for a walk and as I was making my way back I came upon a man stretched over a rock gazing through binoculars at the Royal Yacht. I asked, 'Have you seen much?'

''Not a thing,' he replied. 'I've been staring for more than half an hour and I've not seen the Queen once.'

''Maybe she's out for a walk,' I said, before carrying on down.'

Oh! It's Yersel', Ya Bugger! by the Reverend Jack Kellet, is published by Troubador priced £10.99.