Archie Harrison and Lilibet Diana, the children of Prince Harry and Meghan Markle, are allegedly set to receive royal titles from King Charles III.

The new ruler will bestow the titles of Prince and Princess on them. There is, however, a catch.

King Charles III will only do this if he believes he can put his faith in the Duke and Duchess of Sussex.

The "trust" hinges on whether Prince Harry would publish or withdraw his impending tell-all memoir.

According to royal expert Katie Nicholl, "there is a proviso and that caveat is trust."

As of this writing, it is still unknown what the Duke of Sussex's book is about. However, he previously stated that it will include his mother, Princess Diana, his life in the royal family, his marriage to Meghan Markle, and his departure from the royal family.

Many believe he will divulge royalty secrets and trash talk his royal kin.

Nicholl stated in an episode of "The Royal Beat" that the Sussexes' children are still identified as "master" and "miss" on the royal website. Following the death of Queen Elizabeth II, they are legally entitled to the His/Her Royal Highness titles as the monarch's grandchildren.

Everyone is debating if Archie and Lilibet will be formally recognized as Prince and Princess, according to Nicholl. "And I'm informed that it is a very clear indication from the King," she said, "that he is prepared to bestow those titles, but with a proviso, and that caveat is trust. They have to know that they can trust the [Sussex] family."

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Archie and Lilibet were far down the line of succession when they were born due to rules enacted by King George V in 1917.

But now that King Charles III is the new king, they are considered his grandchildren rather than the Queen's great-grandchildren and are entitled to use the titles Prince and Princess, as well as HRH.

They will not, however, get the HRH titles as claimed because their parents are non-working royals.

According to royal expert Phil Dampier, permitting the Sussex children to be a prince and princess would be a "typical compromise," similar to what happened after Princess Diana and Rebecca Ferguson's divorces.

"Harry and Meghan should be thrilled since using prince or princess sounds nice in the United States; but, even if their children are still high up in the line of succession, they will not be working royals, so it's quite reasonable that they should not hold [HRH] titles."

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