The source told us: “Zara is taking an active role in helping her mother recover from the accident. The Tindalls live a stone’s throw away [on the Gatcombe Park estate], so Zara is always on hand to pop over to make sure Anne has everything she needs.

“Mike and the grandchildren also make regular visits to make sure that everything is kept as ‘normal’ as possible for Anne. Tim is also proving a great support.

“There’s a shift rota in progress to make sure there is always someone with her at any given time.”

Anne’s medical team have said her injuries are consistent with potential impact from a horse’s head or legs, with an air ambulance arriving on the evening of June 23 to take her to hospital.

The Princess has been forced to cancel a series of engagements, including an appearance at the Japanese State Banquet hosted for Emperor Naruhito and Empress Masako last month.

She was also unable to travel to Canada for a First World War commemoration event which left her “deeply saddened”, as she expressed in a statement.

Her remarks were read out by Canada’s Governor General: “It is with deep regret that I am unable to be with you today, as you commemorate the brave efforts and sacrifices of the members of the Newfoundland Regiment who went into battle on the first day of the Somme.

“I have fond memories of joining you in 2016, on the 99th occasion that the people of this Island commemorated the Battle of Beaumont Hamel, and I am deeply saddened that I’m unable to join you again, and I send you my warmest best wishes on this special day of commemoration.” Buckingham Palace has been asked for comment.