So, will Prince Harry and Meghan Markle attend the coronation or ......?

The King's big day is less than a month away, but no one seems to know if the Duke and Duchess of Sussex will be attending from California.

But according to one royal expert, if Harry really wants a filial reconciliation, he has no choice but to show up at Westminster Abbey on May 6.

"If Harry doesn't show up, he will never be forgotten. Writer Tom Quinn told the Express. 'How could he not come to his father's coronation, to the king's coronation? There is no turning back now."

Quinn acknowledges that there are understandable reasons for the Sussexes not to attend, but he does not believe it will work for the royal family.

"They may come up with plausible reasons, such as they are worried about security or their children. [but there are some things they can never sell, no matter how great their PR is, and they can't sell them.

For Quinn, whether the Sussexes come to the coronation or not, their shadow will overshadow the day because people are mindful of the feud between their royal families.

"What should be the focus of the coronation and telling the world that another generation is coming and the royal family is still there will be overshadowed by this tussle with Harry and Meghan," the author argued.

The Sussexes have had a difficult relationship with the entire royal family since they retired from their senior royal roles, moved to California, and made shocking revelations in various media projects. Prince Harry's memoir, Spare, even reportedly led Prince Charles to remove Harry and Meghan from Frogmore Cottage in Windsor.

With this background, it is not surprising that Quinn considers the coronation to be the final test of their family relationship.