Daena Borrowman, a advertising and marketing supervisor at jewellerybox instructed Express.co.uk: “Royal ladies will not be permitted to put on brilliant or darkish nail paint on their fingernails. Only nude shades, sheer whites and light-weight pinks are allowed.”

Also, she added “fake nails or colour nail polish is deemed vulgar by the Royal Family”. Sarah Gibson Tuttle, founder and CEO of Olive & June, commented: “The Royal Family tends to favour sheer, impartial shades on shorter, squoval-shaped nails.

“It’s a super-classic, clear look. It seems timeless and royal-appropriate. While we’ve all heard rumours of guidelines, I do know royal nails are at all times fairly, polished, and completely manicured.”

Royal fans, however, loved Princess Sofia’s look and praised her stylish and fun outfit on social media with @unc94gal saying: “Sofia rocked it!”

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