Meghan Markle and Kate Middleton's attire for the Queen’s funeral including veils

ok.co.uk:

Kate Middleton and Meghan Markle have strict fashion rules they have to follow for the funeral of Queen Elizabeth II. The late monarch will be laid to rest on Monday 19 September and King Charles III has confirmed it will be a bank holiday to give the nation a chance to grieve and their respects together.

And in the days since the funeral date was confirmed, details about the State Funeral have been released and as per royal tradition, much of it is steeped in history.

One of them is surrounding fashion, and the Princess of Wales and Duchess of Sussex have a particular dress code to follow. For all of the latest updates, sign up for OK!'s Royal newsletter.

Aside as well as wearing all black, both will also be sporting traditional black lace mourning veils in some form, as this has been a routine at royal funerals for decades.They are typically crafted from lace, tulle, or fine netting material that allows a person to see through it.