Prince Andrew was the only one who did not wear a military uniform during Queen Elizabeth II's prayer service.

On Monday, Queen Elizabeth II's children - King Charles III, Princess Anne, Prince Andrew, and Prince Edward - joined the funerary events in Edinburgh, Scotland, as part of the somber march for the late monarch. They walked together behind the coffin, but the public noticed something different about the Duke of York.

As seen in the pictures shared by PEOPLE, all siblings except Prince Andrew, wore military uniforms. As for the Duke of York, he wore a dark suit instead.

The news outlet noted that he is not allowed to wear a similar attire since he is no longer considered a working royal - something Prince Harry also faces.

According to Buckingham Palace, working members are the only ones allowed to be in military uniforms. They need to follow the dress code in five events: the Service of Thanksgiving, the procession to Westminster Hall, the vigil at Westminster Hall, the State Funeral service at Westminster Abbey, and the committal service.

While Prince Harry will not be allowed to wear the uniform in all those events, Prince Andrew will wear it at the final vigil at Westminster Hall "as a special mark of respect."

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The Duke of Edinburgh stepped down as a senior royal member and was stripped of his military titles and royal patronages when accusations by Virginia Giuffre emerged.

CBS News contributor Roya Nikkhah said, "That's when you're going to start to see the difference, very publicly, in terms of who is a working royal and who is not."

It is different when Prince Philip died. In April 2021, Buckingham Palace said no royal members would wear military uniforms.

Prince Harry "Saddened" After Not Being Able To Wear Military Uniform

Amid the buzz, royal sources told Page Six that Prince Harry might be saddened as he served two hours in Afghanistan and did military duty when he was still a senior royal.

Prince Harry never wore the uniform since the Mountbatten Festival of Music at the Royal Albert Hall in London in March 2020, before he moved to the US with Meghan Markle.

When the Megxit happened, he lost three honorary military titles including commodore-in-chief small ships and diving, honorary air commandant of RAF Honington, and captain general of the Royal Marines.

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