But these days the two women are clearly thick as thieves, frequently photographed out and about together at official engagements, charity events and country gatherings.
And now, on the second day of Royal Ascot, they have proved once again just how close they really are, riding side-by-side in a horse-drawn carriage, smiling and waving happily while wearing matching spearmint green outfits, having colluded once more over their sartorial selections before their appearance to ensure they wore complementary colours.
The duo attended the Berkshire races yesterday in similarly matching pinks and corals.
The Queen and Camilla, Duchess of Cornwall,
arriving at the second day of Royal Ascot in their complementary
spearmint outfits, pearls and white gloves
The Queen waving to the crowds on day two of
Royal Ascot, wearing a spearmint green overcoat, a lilac floral silk
scarf, a green, pink and purple hat with floral embellishment, a string
of pearls, pearl earrings, white gloves and a diamond brooch
Moreover, she managed - without realising - to scupper the bookmakers hopes of low payouts to people who bet on what colour outfit and hat she would be wearing.
By wearing a jolly, multicoloured headpiece, Her Majesty ensured that everyone who guessed she would appear in either pink, purple or green headgear would receive winnings.
Bookies were similarly put-out yesterday when the Queen wore a coral ensemble and officials at Ladbrokes couldn't decide whether it was peach or pink... so paid out on both.
Jessica Bridge of Ladbrokes said: 'We think Her Majesty is taking us for a ride. These double and triple payouts are giving us a major headache but the Queen is coining it in for her loyal supporters.'
Blue is now the favourite to be her colour of choice on Ladies' Day tomorrow at 3/1, or it's a 4/1 chance she opts for a summery yellow number.
'It seems unlikely but it's 100/1 she throws us another curve ball with a patriotic Union Jack-themed hat,' said Ladbrokes.
Bookies were similarly put-out yesterday when
the Queen wore a coral ensemble and officials at Ladbrokes couldn't
decide whether it was peach or pink... so paid out on both.
The Queen caught during a moment of quiet contemplation, left, and Camilla enjoying the Royal procession, right
The Royal party makes their way towards the box as racing horses trot behind them
Bathed in brilliant summer sunshine, the Queen's carriage processed along the course on day two of the five-day event.
The Queen is a keen horse-breeder and owner who attends Royal Ascot most years - but she has also become the focus of betting attention.
Racegoers traditionally have a punt on the colour of the hat she will wear on Ladies' Day, being staged tomorrow, when female racegoers wear even more outlandish hats and outfits then usual.
Like Ladbrokes, bookmaker Coral also believes she will wear a blue hat and makes the colour its 3-1 favourite. But punters have been backing purple and its odds have fallen from 8-1 to 5-1.
Spectators eagerly photograph the Royal party as they ride past the enclosure on the way to their Royal box
The lofty Royal carriage wheels past the public enclosure carrying the Queen and the Duke and Duchess of Cambridge
Prince Charles and friend ride with the Queen
and the Duchess of Cornwall in the Royal Ascot procession on he second
day of the meet in Berkshire
The Queen and Camilla in their matching spearmint green racing
A Coral spokeswoman said: 'Betting on the colour of the Queen's hat remains hugely popular amongst punters and after predicting pink on day one, they seem to be feeling confident about investing their money in purple.'
The carriage procession also featured the Duke and Duchess of Gloucester and was warmly greeted by the crowds in the stands as it passed by.
Also accompanying the senior Royals in their box - but arriving in a separate carriage - were Prince Edward and his wife Sophie, Countess of Wessex, who looked serious in a smart, mid-sleeve beige wrap-dress with a brown belt, a matching hat with a purple tuile, and nude court shoes.
Lady Helen Taylor, first cousin once removed of the Queen, also attended wearing a fitted block-colour dress of yellow, purple and white.
Sophie, Countess of Wessex, arrived at Ascot in a beige wrap dress, nude courts and matching hat with purple tuile
Lady Helen Taylor, first cousin once removed of
the Queen, chose bold colours on a fitted dress and a small turquoise
hat with matching nails
Lady Helen Taylor greets a friend, left, and the Duchess of Gloucester looks immaculate in countryside chic
Some racegoers attracted gasps from passers-by for all the wrong reasons. Many women chose the hottest day of the year to strip down into minimal ensembles, drawing more attention than those who had spent a fortune on hats.
Last year Royal Ascot introduced strict new fashion guidelines in a bid to smarten up the five day event, but today many female racegoers appeared to be breaching the rules.
As the sun came out, so did the legs on day two of Royal Ascot
Hats as far as the eye can see at the Berkshire meet
Mrs Rose - an Ascot regular of 32 years - was barred from entry to the exclusive section of the course despite having a ticket.
Instead she was told she would only be admitted to the Grandstand because her carefully selected dress was sitting too high above the knee.
The furious 52-year-old Londoner, who is always a firm favourite of the photographers that gather of the five day event, said that she would be seeking compensation and considering legal action.
She branded Ascot staff rude and claimed that she was being victimised because of her profession.
Tracy Rose was outraged to have been evicted
from the Royal Enclosure for not abiding by the dress rules, and is
considering legal action
She said: 'I believe I am being personally
victimised as I have seen people dressed far more extremely than myself
and I will be seeking compensation and maybe taking legal action'
'I think that I am being victimised because I am a hat designer and I come hear wearing one of my designs and they claim I am advertising myself. There are thousands of designers here wearing their hats and clothes.
'I believe I am being personally victimised as I have seen people dressed far more extremely than myself and I will be seeking compensation and maybe taking legal action.'
Mrs Rose is a firm favourite with the Ascot set and is a regular at the five day event, which is attended by the Queen.
Pictures of her strutting her stuff in her unique designs at the summer social event are regularly picked up by the world's media.
'I am being victimised because I sell hats but Royal Ascot is traditionally about hats. I've been coming 32 years and this is the first time I have been turned away. The staff were so rude. I would give them zero out of five for services.
'Once you get in the Royal Enclosure the staff are an absolute delight. We have been coming for so long that some we class as friends.
Last year Ascot launched a new dress code to make sure punters were wearing appropriate attire. A official guide to the event said: 'Royal Ascot is a unique, stand alone event in the sporting calender and dressing accordingly is part of the experience.'
In the Royal Enclosure formal wear is a requirement and dresses should be of a modest length, which is defined as falling just above the knee or longer.
Fellow racegoer Sophie Lassman, aged 23 years, who was also viewing the action from the Royal Enclosure was in favour of the strict rules.
'I think it has made a really positive difference and as a whole Ascot is a lot classer. I think they should actually make the grandstand stricter as well.'
Many racegoers were seen as they tried to enter the course pulling desperately yanking down their skirts and dresses as they caught the attention of the fashion police.
