Queen Elizabeth II Attends The Royal Windsor Horse Show 2018 at Home Park on May 11, 2018

Queen Elizabeth in a quilted popper-front navy jacket from British label David Barry, teamed with silk headscarf and dark sunglasses, as she attends the third day of the Royal Windsor Horse Show 2018 in Windsor, England.

Queen Elizabeth II attends the third day of the Royal Windsor Horse Show 2018 in Windsor, England.

Queen Elizabeth II attends the third day of the Royal Windsor Horse Show 2018 in Windsor, England.

Queen Elizabeth II attends the third day of the Royal Windsor Horse Show 2018 in Windsor, England.

Queen Elizabeth II attends the third day of the Royal Windsor Horse Show 2018 in Windsor, England.

Queen Elizabeth II during day three of the Royal Windsor Horse Show at Windsor Castle, Berkshire.

Queen Elizabeth II during day three of the Royal Windsor Horse Show at Windsor Castle, Berkshire.

Queen Elizabeth II during day three of the Royal Windsor Horse Show at Windsor Castle, Berkshire.

Queen Elizabeth II during day three of the Royal Windsor Horse Show at Windsor Castle, Berkshire.

Queen Elizabeth II during day three of the Royal Windsor Horse Show at Windsor Castle, Berkshire.

Queen Elizabeth II with Prince Andrew, Duke of York at the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

Queen Elizabeth II and King Hamad bin Isa Al Khalifa of Bahrain attend the Royal Windsor Endurance event at the Royal Windsor Horse Show in 2018 at Home Park in Windsor, England.

Queen Elizabeth II attends the Royal Windsor Endurance event at the Royal Windsor Horse Show in 2018 at Home Park in Windsor, England.

Queen Elizabeth II attends the Royal Windsor Endurance event at the Royal Windsor Horse Show at Home Park on May 11, 2018, in Windsor, England.

King Hamad bin Isa Al Khalifa of Bahrain attends the Royal Windsor Endurance event at the Royal Windsor Horse Show at Home Park on May 11, 2018, in Windsor, England. 

King Hamad bin Isa Al Khalifa of Bahrain attends the Royal Windsor Endurance event at the Royal Windsor Horse Show 2018 at Home Park in Windsor, England.

King Hamad bin Isa Al Khalifa of Bahrain attends the Royal Windsor Endurance event at the Royal Windsor Horse Show 2018 at Home Park in Windsor, England.

Queen Elizabeth II during day three of the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

Queen Elizabeth II during day three of the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

Queen Elizabeth II during day three of the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

Queen Elizabeth II during day three of the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

Queen Elizabeth II with the King of Bahrain Hamad bin Isa Al Khalifa during the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

Queen Elizabeth II talking to Prince Philip, Duke of Edinburgh during the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

Queen Elizabeth II, casually dressed in a quilted navy jacket, tweed skirt, and floral headscarf, looked delighted to have her husband back at her side while Prince Philip, Duke of Edinburgh appeared in good spirits

Queen Elizabeth II talking to her husband Prince Philip, Duke of Edinburgh during the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

Prince Philip, Duke of Edinburgh smiles at the Royal Windsor Horse Show on Friday, May 11, 2018. Speaking about the Duke's miraculous recovery this week, a source told The Sun: 'When he sets his mind to something he gets on and does it. He has been walking up and down stairs several times in succession. He has also been charging across rooms at full speed. He even had to be told to slow down'

Prince Philip, Duke of Edinburgh, who appeared to be wearing a hearing aid, popped on a pair of spectacles at one point as he drove himself around the castle grounds on Friday morning May 11, 2018 - before stopping to chat to his wife Queen Elizabeth II (not pictured)

(R) Queen Elizabeth II looked to be in excellent spirits as she chatted to fellow equestrian lovers at the annual event, which comes to an end on Sunday, May 13, 2018. The Queen kept warm with a navy blue quilted jacket, teamed with a pair of oval sunglasses

The beaming Queen Elizabeth II could be seen admiring the thoroughbreds after arriving for her second day at the Royal Windsor Horse Show 2018. Held in her own backyard, the castle grounds will play host to the wedding of the year next weekend

Queen Elizabeth II, clad in dark sunglasses, a silk headscarf, and a quilted jacket, the Queen could almost have passed for a ticket-holding spectator at the Royal Windsor Horse Show 2018

Queen Elizabeth II was no doubt delighted to be joined by her husband after his recent hip operation, as they attend the third day of the Royal Windsor Horse Show 2018 in Windsor, England.

Queen Elizabeth II attends the third day of the Royal Windsor Horse Show on May 11, 2018, in Windsor, England. The Royal Windsor Horse Show is hosted in the private grounds of Windsor Castle and is attended by members of the Royal family including the Queen.

(C) Queen Elizabeth II, 92, could be seen sharing a laugh with fellow guests as they examined the schedule of events together. One of the spectators appeared to have highlighted some of the main events in yellow

The Coaching Marathon makes its way along the Long Walk on the third day of the Royal Windsor Horse Show on May 11, 2018, in Windsor, England.

 Prince Philip, Duke of Edinburg, 96, was spotted chatting to his wife Queen Elizabeth II through the window of a private car as day three of the annual equestrian event got underway this morning and appeared to be in good spirits

Queen Elizabeth II talking to Prince Philip, Duke of Edinburgh during the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.  It was claimed last night that The Duke of Edinburgh, who retired from public duties in August 2017, had ditched his crutches 'just in time' for the wedding of the year as a royal insider praised his 'amazing willpower'

(R) Prince Andrew, Duke of York who lives just a stone's throw away from the event at the Royal Lodge, Windsor, could be seen watching the action intently as he chatted with the King of Bahrain Hamad bin Isa Al Khalifa on Friday afternoon, May 11, 2018

The thrifty Queen Elizabeth I surprised onlookers when she stepped out in a £69.99 quilted popper-front jacket from British label David Barry. Her Majesty teamed hers - which features a slightly different tartan piping to the version listed online - with a tweed skirt, silk headscarf, and Launer handbag, as she watched the action unfold at the Royal Windsor Horse Show 2018.

The Duke of Edinburgh was admitted to the private King Edward VII Hospital in early April for surgery after a month of severe discomfort on the advice of doctors. Prince Philip, Duke of Edinburgh talking to his wife Queen Elizabeth II during the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire, pictured.

Prince Philip, Duke of Edinburgh, on being discharged from hospital last month, it seems the 96-year-old, who is likely to still be using walking sticks or crutches at this stage, was keen not to be seen incapacitated so left ten days later after a prolonged rest. Pictured here with his wife Queen Elizebeth II on left and with Lady Penny Romsey during day three of the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

At the Royal box: Queen Elizabeth II was joined by VIP guests including the King of Bahrain, Hamad bin Isa Al Khalifa, left, and her son Prince Andrew, Duke of York, center, during day three of the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

Queen Elizabeth II talking to Prince Philip, Duke of Edinburgh during the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire. While it is not known if Prince Philip will enjoy the day's festivities on foot, the 96-year-old Duke's surprise appearance is the strongest indication yet that he is firmly on the mend.

Queen Elizabeth in a quilted popper-front navy jacket from British label David Barry, teamed with silk headscarf and dark sunglasses, as she attends the third day of the Royal Windsor Horse Show 2018 in Windsor, England.

(L-R) Queen Elizabeth II, casually dressed in a quilted navy jacket from British label David Barry, tweed skirt, and floral headscarf, looked delighted - pictured here with Lady Penny Romsey who is the wife of the Queen's cousin Lord Brabourne

Prince Philip, Duke of Edinburgh, refusing to miss out on the fun in spite of his condition, the elderly Duke, dressed in a navy jacket bearing a Royal crest, watched the action through a pair of binoculars at one point, after an aide brought him a programme of events to read during the Royal Windsor Horse Show in 2018 at Windsor Castle, Berkshire.

Prince Philip, Duke of Edinburgh - who has reportedly surprised and delighted his loved ones with his remarkably quick recovery - didn't need his spectacles to read through the program of events after it was offered by one of his fellow spectators during the Royal Windsor Horse Show 2018 at Windsor Castle, Berkshire.

The Coaching Marathon is one of the most glamorous and competitive events on the Royal Windsor Horse Show 2018 lineup. The annual event is the only time of the year that guests are allowed into the palace's beautiful grounds

The Coaching Marathon makes its way along the Long Walk on the third day of the Royal Windsor Horse Show on May 11, 2018, in Windsor, England. The Royal Windsor Horse Show is hosted in the private grounds of Windsor Castle and is attended by members of the Royal family including the Queen.

VIP visitors don their glad rags for The Coaching Marathon, one of the flagship events of the show, as the procession makes its way along the Long Walk on the third day of the Royal Windsor Horse Show