It is still uncertain whether the Duke and Duchess of Sussex will attend the event at Westminster Abbey on May 5th, 2023. If they do attend, they may not wear the same robes or coronet as the rest of the Royal Family.
Historian Dr. Tessa Dunlop explained to the Mirror that the pair would likely attend in their own attire, with Harry possibly without a coronet and robe.
Dunlop noted that working royals would stand out at the coronation, as exemplified by Princess Margaret's coronation gown, designed by Norman Hartnell and offset with a Cartier tiara.
Dunlop also suggested that William and his children would likely sit alongside the Queen Mother, with the Sussexes in a different section.
Overall, Dunlop emphasized that the event would be all about royal hierarchy, with "visual messaging through both costume and carriage" reminding everyone of who the future King and Queen are. Prince Harry was famously not allowed to wear military uniform for the late Queen's funeral, but was permitted to do so at a lying-in state vigil.