The UK's Press Association said the decision is understood not to have been taken for health reasons and was mutually agreed by the Queen and Louis' parents, the Duke and Duchess of Cambridge, some time ago.
The sovereign and Prince Philip will return to London from the monarch's private Sandringham estate in eastern England on Monday.
The cheeky pair, who welcomed little brother Prince Louis in April, were spotted at the window of Buckingham Palace watching the RAF 100 flypast at around 1pm.
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In a White House statement, the press secretary said that the Hammonds' five-year prison sentences had been "unjust". The move by Trump raised concerns that others would be encouraged to actively oppose federal control of public land.
And Louis' non-royal godparents will have influence on the little prince.
Harry, Meghan, William and Kate joined the Queen, other prominent members of the royal family as well as Prime Minister Theresa May at the beginning of a day of events. "She loved all the old classics and Harry had the brilliant idea of starting a little library of first editions for Louis, [big sister Princess] Charlotte and [big brother Prince] George to enjoy as they get older", a friend told the tabloid. Coincidentally, William and Kate attended the wedding of Robert and Hannah on their own one-year wedding anniversary in 2012.
The cream lace and white satin robe is a replica of the robe made for Queen Victoria's eldest daughter in 1841, which is now too delicate to be worn.
Welby, who will baptise the baby by pouring holy water from the River Jordan over his head, said the event would be "very nerve-wracking" but "a great privilege".
They include the Duchess' cousin Lucy Middleton and Guy Pelly, a childhood friend of William's. Fletcher is also a close friend of William's, and the two went to both prep school and Eton College together. There, the couple will honor their guests by serving a slice of of christening cake, which, Kensington noted, "is a tier taken from The Duke and Duchess of Cambridge's wedding cake".