Prince George, 7, is currently the third in line to the British throne after his grandfather, Prince Charles, and his father, Prince William, but there's a risk that he might not get his chance to be the monarch when he is of age, as predicted by a royal expert.

According to royal author Clive Irving, much could change in the monarchy by the time George is primed to rule the United Kingdom. His great-grandmother, Queen Elizabeth, is still of sound mind and health to rule over her subjects 69 years on. Charles is 72 and still waiting to sit on the throne. Before George becomes king, he also has to wait for his father's turn.

Irving said that three royal reigns will run their course before George can be crowned. By then, the interest in the monarchy could die and Irving believes that its survival will be at risk under the reign of Charles.

In his book The Last Queen, Irving said that Her Majesty has been an exemplar ruler just like her father, King George VI. He doubts that Charles will be the same because he falls short of the standards set by the monarchs before him.

Irving also said that polls have shown a waning public interest in the monarchy under Charles' rule. In a survey from YouGov, 67 percent believes that Britain must continue the monarchy while only 21 percent said that the head of state must be elected. On the other hand, 41 percent think William should be the next king instead of Charles (37 percent) but the Prince of Wales is still very popular with the over 65s.

The royal author said that the public is generally not inclined to support the royal family if they have "too many freeloaders." Working royals receive financial support for their lifestyle from public funding through the Sovereign Grant.

Charles, however, has been rumored to pare down the roster of working royals once he becomes the king. He prefers just his direct line -- William and his wife, Kate Middleton, and their children George, Princess Charlotte and Prince Louis -- to work for the monarchy. But Irving said that it's not possible to judge this system for now even if it could work to appease the public, in theory.

Early on, George and his siblings have been training for their future roles as public servants. According to People, the Cambridge children have had some engagements in 2020, despite the pandemic year.

They joined in the Clap for Carers movement in March 2020 and delivered food packs with their parents to the vulnerables in the Norfolk community in April.

They had their first public speaking appearance in October to questions about animals to naturalist Sir David Attenborough. The kids had their very first red-carpet debut in December to watch a special show at the London Palladium with the families of NHS frontline workers.

While George has yet to take on his first solo royal engagement, insiders said that William and Kate plan to increasingly involve their children in their work this year. However, like his father, George is not expected to have his first public engagement until he is in his 20s.