Prince Harry and Meghan Markle's children, Archie, 3, and Lilibet, 1, were born without the title, but now that their great-grandmother, the Queen, has died, this situation has changed.

King George V, grandfather of Queen Elizabeth II, established a convention that all children and grandchildren of British monarchs are automatically entitled to use the title "Prince" or "Princess" and also the title "HRH" - His or Her Royal Highness - (as in "HRH Prince William") The terms of the agreement were established that he would be given the title "HRH" - His or Her Royal Highness.

Upon his mother's death, her eldest son automatically became Charles III, and Archie and Lilibet became the monarch's grandchildren. This means that they are entitled to take the names Prince Archie and Princess Lilibet and use the designation HRH, as reported by The Guardian.

Whether the Duke and Duchess of Sussex will choose to call their children by these new royal titles in official communications is another matter, Hello! points out.

When Archie was born, it was suggested that he take the title of Earl of Dumbarton, but his parents reportedly refused because his name contained the word "dame."

Prince Charles may decide to revoke Archie and Lili's rights to these royal titles.

Prince Harry and Meghan Markle have retained their HRH titles since relinquishing their royal duties in 2020, but are prohibited from actively using them, according to People. This is another plausible reason for Prince Charles to want Archie and Lili not to use their HRH titles, but this too remains to be seen.