Princess Kate, who's continuing chemotherapy following her cancer diagnosis, is said to be worrying about Princess Anne's injuries.
Prince William, who's said to be rushing to hospital with his cousin Zara Tindall, reportedly informed his wife about the health condition of Princess Royal, who was taken to hospital with minor injuries following an incident on the Gatcombe Park estate on Sunday evening.
"The Princess of Wales has sent best wishes to the King's sister for a speedy recovery as she's being treated in the hospital for minor injuries and concussion, a palace insider has confirmed.
According to health specialists and medical experts, a concussion is a mild traumatic brain injury.
It's effects are often short term and can include headaches and trouble with concentration, memory, balance, mood and sleep.
Concussions usually are caused by an impact to the head or body that is associated with a change in brain function.
Zara Tindall and Peter Phillips' mother Princess Anne Highness remains in Southmead Hospital, Bristol, as a precautionary measure for observation and is expected to make a full and swift recovery.
Anne, who's a full time working royal, was praised as "outstanding" by viewers of Trooping the Colour when she successfully managed to control her misbehaving horse during the procession on June 15. Now, it's being claimed that her injuries are caused by a horse's leg or head.
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