Princess Anne suffered a concussion and minor injuries during an accident in Gatcombe Park and the Princess Royal is currently in hospital.
Princess Anne is expected to return home later this week.
Now royal expert Rebecca English has revealed details of the incident and the nature of the injuries.
Rebecca tweeted: “What we know so far: The princess was walking around her property in Gatcombe Park last night when an incident occurred which left her with head injuries and a concussion.
“The exact cause and nature of the accident are not confirmed, but the injuries are consistent with impact from the head or legs of a horse.”
The royal expert went on to say: “The princess is comfortable in hospital and recovering well. She is hospitalized as a precaution/observation measure. She is expected to make a full recovery and, hopefully, she will return home later this week.”
According GB NewsPrincess Anne's husband, Sir Tim Laurence, as well as their two children, Peter Phillips and Zara Tindall, were in Gatcombe Park at the time.
Sir Tim accompanied the princess to the hospital.
Earlier, Buckingham Palace said in a statement: “The Princess Royal has suffered minor injuries and a concussion following an incident on the Gatcombe Park estate.
“His Royal Highness remains in Southmead Hospital, Bristol, as a precautionary measure for observation and is expected to make a full and speedy recovery.”