The Kate effect has been credited with boosting the bottom line of many businesses including Zara, Top Shop and Reiss, who have all seen their sales soar after their clothes were worn by Kate.

Now, it appears, a similar Kate-inspired boost is happening to her father-in-law's business.

For Prince Charles's company has cashed in on the popularity of Kate Middleton and baby George by selling a range of baby goods including organic baby food and baby clothes which has increased a turnover in his company by almost £1m in the past year.

"The Duke and Duchess of Cambridge's popularity has given the royal family a lift in general," a courtier tells the Daily Telegraph. But Charles, in particular, has capitalized on this by selling a range of souvenirs at his shops including the one at his Highgrove estate in Gloucestershire, commemorating George's birth.

According to accounts lodged at Companies House, the company that sells the goods at Charles's shops made profits of £652,000 in the year until the end of last March, compared to the £608,000 in the previous 12 months.

The results mean the company was able to donate £689,000 to the Prince of Wales’s Charitable Foundation, an increase of 11.5 per cent on the previous year.