Royal fans spot odd detail in photo of Kate Middleton and King Charles' first post-scandal joint outing

Kate Middleton and King Charles have carried out their first joint engagement together after being named as the royals who allegedly expressed 'concerns' over the colour of Meghan Markle and Prince Harry's son Archie's skin.

The two senior royals, accompanied by Prince William and Queen Camilla, pulled out all the stops for a Diplomatic Reception at Buckingham Palace, with both royal women delighting fans by donning tiaras for the occasion.

The Princess of Wales looked stunning in a pink sequinned Jenny Packham gown, which she paired with the Lover’s Knot Tiara, while Queen Camilla donned a cream embroidered evening coat with the Girls of Great Britain and Ireland Tiara.

RELATED:

• Royals 'desperate' to quash rumour William cheated on Kate with longtime friend

• Prince William reveals he’s a secret Taylor Swift fan

• Piers Morgan names two senior royals accused of racism in Omid Scobie's Endgame book

And royals fans have spotted an odd detail in the snap, with many questioning why Kate is the only one wearing her sash on a different side to the others.

"Why does Catherine's sash go the other side??" one fan asked, with another asking: “Serious question. Why is Katherine's sash going the opposite direction from the others?”

It turns out there is a pretty simple reason, with a few very informed royal fans answering the question.

"Princess of Wales wears Royal Victorian order and the rest of them wear Order of the Garter. This is the way they have been worn,” one person wrote.

“The King, The Queen, and The Prince of Wales are wearing the sash of the Order of the Garter which goes from the left shoulder to right hip and The Princess of Wales is wearing the sash of the Royal Victorian Order which goes from the right shoulder to the left hip,” another person wrote.

The royals’ official appearance comes just days after TV presenter Piers Morgan revealed on his show, Piers Morgan Uncensored, that Kate Middleton and King Charles were named in the Dutch version of Omid Scobie’s book, Endgame, as the royals who allegedly questioned what colour Prince Archie’s skin would be when he was born.

Piers said: “I don’t believe any racist comments were ever made by any of the royal family and until there is actual evidence of those comments I will never believe it”.

Piers said he wanted to "cut through all this crap" and name the family members.

"Frankly, if Dutch people wandering into a bookshop can pick it up and see these names, then you, British people, here — who actually pay for the British royal family — you’re entitled to know too," he said. "And then we can have a more open debate about this whole farrago. Because I don’t believe any racist comments were ever made by any of the royal family — and until there is actual evidence of those comments being made I will never believe it.

"But now we can start the process of finding out if they ever got uttered, what the context was, and whether there was any racial intent at all. Like I say, I don’t believe there was. The royals named in this book are…”

Never miss a thing. Sign up to Yahoo Lifestyle’s daily newsletter.

Or if you have a story idea, email us at lifestyle.tips@yahooinc.com.