WATCH: Kate Middleton holds Princess Charlotte's hands as they arrive at Queen's funeral
The two young royals will walk through the church in procession behind the late monarch's coffin as the military bearer party carries it. The future king and his younger sister will be side-by-side with their mother and father, followed closely by the Duke and Duchess of Sussex.
Prince William and Princess Kate's two eldest children joined their parents
The royal couple's youngest child Prince Louis did not join his older siblings. There is no official rule that states children under a certain age are forbidden from attending the funeral of a Sovereign, though those very young may be permitted to stay at home given the emotional gravity of the historic day.
The siblings were pictured at Westminster Abbey
When asked how her children were coping after losing their great-grandmother, Kate revealed last week that "the children are doing well and they are being looked after at school."
The two youngsters made an appearance at the Queen's funeral
However, one crowd member was told George was said to understand the loss of his great-grandmother more than his younger siblings. One well-wisher also explained: "She said they were keeping things as normal as possible for the children.
"She says the children were settling in well to their new school and Kate was grateful for the support. I joked I had to be quick because I had to do the school run and she said she was heading back to London to do it as well."
The brother and sister walked between their parents in the procession
The royal couple's three children are nine, seven and four. They started at their new school on 8 September which was the same day Her Majesty died aged 96 at Balmoral. When reports broke of the Queen being ill, Prince William rushed to Balmoral to see his grandmother, while his wife Princess Kate remained in Windsor to collect the children from school.
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