Queen and Prince Charles in rare photograph together in the gardens of Frogmore House
The Queen clearly enjoyed her elder son's company as they took a stroll in the spring sunshine during one of his several visits to Windsor.
The rare photo of Her Majesty and Prince Charles was taken at Frogmore House, sometimes described as the Royal Family's "secret bolt-hole", in Windsor's Home Park, just a stone’s throw from Windsor Castle, where the Queen and the Duke of Edinburgh have spent most of the last year in lockdown.
Recently, as rules have eased, the Queen, 94, has received visits from various members of the family, spending time with them outdoors as the weather improved.
The Prince of Wales, 72, is understood to have made several visits from Highgrove, although palace sources stressed they had always complied with Government guidelines.
As the Duke, 99, continues his recovery from heart surgery and a month-long stay in hospital, the Queen has relished the company.
In 2017, the monarch described her love of the gardens at Frogmore, which is around 10 miles away from Heathrow Airport, during a special message for Radio 4's Gardeners' Question Time.
She told of the "special place" it has in her family's hearts, and her early memories of her mother as a "hands-on" gardener.
“Indeed, I would echo the sentiments of Queen Victoria, who, 150 years ago, wrote of this dear lovely garden where all is peace and you only hear the hum of bees, the singing of the birds,” she said.
“These days, there is more noise from the air than in 1867, but Frogmore remains a wonderfully relaxing environment."
She added: "I'm not any sort of expert on gardening, but plants, trees and flowers have been a source of pleasure throughout my life."
John Anderson, the keeper of the gardens at Frogmore House, confirmed that the Queen took a personal interest in every element of the garden and spent most time there in the spring.
"When it comes to Frogmore, because it's such a special garden, I will often have a meeting with Her Majesty, take a walk around the gardens and put ideas out of things I hope she will like,” he said.
“If she approves we will get on and do the work and hopefully she will enjoy it."
He disclosed the Queen particularly liked primroses, wild flowers and bright colours, and also took an interest in the wildlife.
In spring, Mr Anderson said the garden is filled with daffodils, tulips and azaleas.
A cherry tree avenue planted near the tea house allows visitors to enjoy afternoon tea whilst “looking out at this beautiful little grove of cherry trees".
Asked whether the Queen ever donned gardening gloves and got involved with a trowel, Mr Anderson laughed: "I think she'd leave that role up to His Royal Highness, the Prince of Wales."
Frogmore was the venue for the Duke and Duchess of Sussex’s wedding reception, playing host to 200 of the couple’s closest friends in May 2018.
One of their official engagement portraits was taken on the outdoor steps of the house.
Princess Eugenie and Jack Brooksbank are understood to be renting the couple’s Frogmore Cottage, on the other side of the gardens, which will allow the Queen plenty of access to her great-grandson, August, born in February.
Frogmore House is also the burial place of Queen Victoria and Prince Albert, and a honeymoon destination for the future George VI and Queen Elizabeth, the Queen Mother, in 1923.
