Queen Camilla will be the most high-profile public face of the British monarchy as her husband King Charles III and his daughter-in-law recuperate from surgery.
Charles, 75, spent three nights in hospital recovering from an operation on an enlarged prostate, and was discharged on Monday.
Catherine, Princess of Wales, 42, also had abdominal surgery at the same private clinic, and is now back home with her husband, Prince William, and their three children.
With Charles and Kate facing weeks of rest and recuperation, and heir to the throne William, 41, tending to his wife, the burden of public engagements has now fallen largely on the 76-yearold queen.
It also means greater roles in the short term for the king's only sister, Princess Anne, 73, and the younger of his two brothers, 59-year-old Prince Edward.
Charles's recuperation could last up to a month, according to media reports, while Kate is expected to be out of action until at least Easter on March 31, her Kensington Palace office has said.
The king has won plaudits for being open about his condition but no reasons have been given for Kate's admission to hospital, although officials said it was not linked to cancer.
Camilla visited Charles every day during his brief stay in hospital, despite a busy schedule.
On Tuesday, she hosted a reception at Windsor Castle, for authors, illustrators and bookbinders working on a collection of miniature books for the centenary of Queen Mary's Doll's House.
This week she has three engagements, including two outside London.
Edward last week spent four days on the remote British overseas territory of Saint Helena, some 2,000 kilometres (1,200 miles) west of Angola.
He inaugurated a new international airport, planted a tree and met 191-year-old Jonathan, the volcanic tropical island's resident giant tortoise.
His wife Sophie stayed in London and undertook several engagements.
The Duke and Duchess of Edinburgh, as they are formally known, are not royal big hitters with the public.
Anne, also known as the Princess Royal, is more popular but her activities do not garner much press coverage.
Last week, she visited a prison in Norfolk, eastern England, and opened a new sailing centre. She also stood in for her elder brother at an investiture ceremony at Windsor.
Opinon polling indicates that younger people are less interested in the British monarchy and the current situation robs the institution of its two star younger members.
Both had been expected to attend the BAFTA film awards -- the biggest night in British cinema -- in February, and reportedly also visit Rome.
William, whose mother was the late Princess Diana, is the most popular "working royal", with a 68-percent favourable opinion rating, according to a recent YouGov survey.
Anne was next on 67 percent, followed by Kate on 63 percent. Charles was in sixth place on 51 percent, with Edward on 42 percent and Camilla on 41 percent.
The number of working royals -- a member of the family who represents the king at official engagements -- has dwindled in recent years.
Charles's younger son Prince Harry and his wife Meghan quit royal life in early 2020 when they settled in California.
Prince Andrew -- the king's other brother -- has been sidelined since 2019 because of uproar at his friendship with the late US financier Jeffery Epstein, a convicted paedophile.
Age is also catching up on other members, with the late Queen Elizabeth II's cousin, Prince Richard, Duke of Gloucester, now 79, and his wife, Birgitte, 77.
Two other cousins of the late queen, Princess Alexandra, and Prince Edward, Duke of Kent, are 87 and 88 respectively, and appear increasingly frail.
