The King and his siblings have stood in silent contemplation as they guarded their mother's coffin for a 15-minute vigil at Westminster Hall.
The Queen's children - Charles, the Duke of York, the Princess Royal and the Earl of Wessex - took part in the vigil on Friday evening. The new sovereign, Anne, Andrew and Edward looked sombre as they took their places at the coffin - four days after they participated in a vigil in St Giles' Cathedral in Edinburgh.
Other members of the royal family, including the Queen Consort, Vice Admiral Sir Tim Laurence and the Countess of Wessex, along with some of the Queen's grandchildren, looked on. All four were dressed in uniform on Friday, with an exception made for disgraced Andrew, who is no longer a working royal, to wear his military uniform as a "special mark of respect" for the Queen.
The late monarch has been lying in state in London since Wednesday and thousands of mourners have filed past to pay their final respects after queueing for hours. On Saturday, the Queen's grandchildren are going to participate in a vigil at her coffin, and the Duke of Sussex will join his brother the Prince of Wales in wearing uniform.
Royal sources said the decision to allow Harry to wear his uniform during the vigil was made by his father. Harry, who saw action on the front line during two tours of duty in Afghanistan, has been denied the chance to wear his military uniform as he publicly mourns, because he is no longer a working royal.
Despite being a former Army officer, he has been in civilian dress for official events, including walking behind his grandmother's coffin on Wednesday when it was carried to Westminster Hall for lying in state. The royal source said William will stand at the head while Harry will stand at the foot.
At the King's request, they will both be in uniform. The other grandchildren will be in morning coat and dark formal dress with decorations. The source said the grandchildren, at the King's invitation, were very keen to pay their respects - just as their parents have done on Friday evening.
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