Prince William and Kate Middleton have recently made a subtle adjustment to their titles.

The Prince and Princess of Wales recently visited Scotland, where they were referred to by additional titles.

Last year, King Charles III granted them new titles, allowing William and Kate to publicly endorse brands they favor.

Royal Warrants are bestowed upon individuals or companies with a significant supply of goods or services to the Grantor's Household over five years within the last seven.

During their visit to Scotland, they were called the Duke and Duchess of Rothesay, a tradition dating back 700 years.

This title, originating in the 14th century, is traditionally passed down to the heir apparent of the Scottish Crown.

Prince George is likely to inherit the Duke of Rothesay title once Prince William becomes King William.

Aside from the Duke and Duchess of Rothesay, they also hold titles as Duke and Duchess of Cornwall and Earl and Countess of Chester.

Eventually, they will ascend to the titles of King and Queen, so they should not grow too attached to their current titles or personalize items with Duke and Duchess designations.