Last week it was revealed that Harry and Meghan had chosen for their children to use their royal titles, which they are now entitled to do so as the grandchildren of the monarch.
The Buckingham Palace website has also now been updated to reflect their wishes.
Ms Seward told The Mirror: “Archie and Lilibet have been allowed to use this style since their great-grandmother died, but their parents have chosen not to until now.
“How interesting they waited six months to do this. They were hoping the Palace would jump the gun and announce it before they did. No such luck.
Another new royal title was unveiled last week as Prince Edward became Duke of Edinburgh, inheriting his late father’s title.
His wife Sophie is now the Duchess of Edinburgh, with his previous title the Earl of Wessex passing to their teenage son James.
Ms Seward outlined the key difference in the two title announcements, with a word missing in one of the statements.
She continued: “The contrast between the way in which Harry and Meghan released the news of their children’s royal titles and the way King Charles announced his brother’s ennoblement was stark.
“King Charles issued a formal statement from Buckingham Palace to say he was ‘pleased’ to confer the Dukedom of Edinburgh upon The Prince Edward, Earl of Wessex and Forfar.
“It was such a grand announcement it felt as if it were in a gilded frame pinned to the Buckingham Palace railings.
“Harry and Meghan on the other hand asked their spokesperson to announce when their 21-month-old daughter Lilibet was christened in Los Angeles last week she would be baptised using the royal style Princess. Archie in turn would use the style, Prince.
“It is so much easier to do things in the traditional style.”
*This story has not been edited by The Infallible staff and is auto-generated from a syndicated feed.