Princesses Beatrice and Eugenie pictured in 2023. The sisters have kept a low profile since shocking revelations about their parents emerged when the Epstein files were released in January

According to sources, Ferguson barely left her first-floor two-bedroom chalet overlooking the stunningly beautiful lake since checking in nearly a month ago, and was never seen on the large balcony.

She ordered all her meals via room service – bresaola beef with mozzarella was a favourite, as was chicken breast.

She was never seen on the resort’s walking trails, or down by the lake, or at its clay tennis courts. Her contact with the outside world was kept to a bare minimum, though she had her hair done on March 24 by a visiting stylist.

Sources close to Fergie say that she remains in constant touch with her daughters, Princesses Beatrice and Eugenie, on the phone, while both of them have been increasingly concerned over her mental health.

Despite the mounting pressure on her, friends describe a woman who is tired but not broken. ‘She just wants a door that doesn’t open for strangers,’ a source said. ‘That’s all it is. She wants to breathe.’

The King’s household has made plain for some time that the duchess is no longer part of official royal life. She is not invited to Sandringham or Balmoral and will never appear on the Palace balcony again.

Despite a disastrous few months for the Mountbatten-Windsors, which culminated with the arrest of Andrew in February, Eugenie and her sister Beatrice are believed to have been invited to Royal Ascot by King Charles.

The sisters are in line for an appearance in the official carriage procession and the Royal Enclosure at the racing festival this June.

Charles is said to be still fond of his nieces despite the astonishing downfall of their father in recent years, and will permit them to attend royal events in future.

It is believed that neither Beatrice nor Eugenie have visited Andrew, 66, during his exile in Sandringham