The Queen’s funeral will be attended by 2,000 people, including Prince George, 9, and Princess Charlotte, 7.
The two children will march with the Royal Family as their great-grandmother’s coffin enters Westminster Abbey, the 13th-century chapel where the state funeral will be placed.
George and Charlotte will follow in their parent’s footsteps, the Prince and Princess of Wales, William and Kate. Following them will come to their uncle and aunt, the Duke and Duchess of Sussex, Harry and Meghan.
The procession will be led by King Charles III and Camilla, the Queen Consort.
George and Charlotte’s younger brother Louis, 4, is not expected to attend.
The Order of Service shows a service filled with traditional church music and readings from the Bible, with a sermon from the Archbishop of Canterbury, Justin Welby.
“I am the resurrection and the life,” will be the reading as the royal procession arrives in the abbey, in a service which the Queen helped to plan.
Prime Minister Liz Truss will read a lesson, with prayers from religious leaders including Cardinal Vincent Nichols, the Roman Catholic Archbishop of Westminster.
The funeral will hear praise for the Queen’s long reign, with the Dean of Westminster, David Hoyle, commending her “long life of selfless service”.