Princess Michael of Kent has suffered two broken wrists after falling down the stairs at her home in Kensington Palace.
The 79-year-old, who is married to the late Queen's first cousin Prince Michael, was carrying an armful of overcoats when she fell.
While she fell into the coats, she broke multiple small bones when she held her hands out to break her fall.
The princess attended King Charles's pre-Christmas lunch at Buckingham Palace on Thursday with her wrists encased in splints.
She told the Daily Mail: "So many things that you rely on being able to do, like cleaning your teeth, are impossible. I can type with one finger on a mobile, but I can’t use a laptop."
She added: "I am told that, after an accident like this, if you do one wrong movement on top of the unhealed bones, you are back where you started."
The royal's accident comes amid a difficult year for her family. In February, Princess Michael's son-in-law, Thomas Kingston, took his own life at the age of 45. He died from a "catastrophic head injury" and a gun was found near his body at his parents' home in the Cotswolds.
The princess addressed Thomas' death in an interview with Majesty Magazine, saying his marriage to her daughter Lady Gabriella was "very happy". "Tom was a lovely man, so kind and thoughtful," she said. "They were very happy together. We often had them here with Freddie and Sophie and the girls for Sunday lunch."
"We never had an inkling anything was wrong," she added.
An inquest held following his death was told that Thomas had initially been given sertraline, a drug used to treat depression, and zopiclone, a sleeping tablet, by a GP at the Royal Mews Surgery, a practice at Buckingham Palace, after complaining of trouble sleeping following stress at work.
He later returned to the surgery saying they were not making him feel better, and his doctor moved him from sertraline to citalopram, a similar drug. In the days leading up to his death, Thomas had stopped taking medication, with toxicology tests showing caffeine and small amounts of zopiclone in his system.
Thomas's widow, Lady Gabriella Kingston, described her marriage as "deeply loving and trusting" and said that he had never expressed any suicidal thoughts to her or others.
She also said that he had been deeply affected by the suicide of a friend and the "devastating impact it had on other people's loved ones".
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