The Queen's funeral took place at Westminster Abbey on Monday 19 September, with most members of the royal family in attendance.
The Prince and Princess of Wales attended with their children, Prince George, nine, and Princess Charlotte, seven, though the royal couple chose to leave their youngest, Prince Louis, at home. Royal fans were quick to take to Twitter to express their concerns for the four-year-old who wasn't allowed to attend his great-grandmother's funeral service.
WATCH: Prince William, Prince George and Princess Charlotte leave with the Queen's coffin
It seems likely that following Prince Louis' unforgettable playful antics at the Queen's Platinum Jubilee celebrations earlier this year, Prince William and Princess Kate made the decision to leave their youngest child at home for the poignant royal occasion.
Though parenting expert Jo Frost, AKA 'Supernanny' previously praised 40-year-old Kate's commendable patience during Prince Louis' cheeky behaviour in the royal box, it seems the couple may have felt it most appropriate for their son to stay at home.
Prince Louis captured the hearts of the nation at the Queen's Platinum Jubilee
Speaking on the young royal's antics at the Jubilee, Supernanny remarked: "All that sitting, watching and organisation, most children can't sit in their chairs at a dining table for longer than 15 mins. It certainly must have been beautifully overwhelming for this little chap, especially with no playtime in between and long days, children are going to test, one should expect as such."
It seems most likely that Prince Louis was left under the Wales family's nanny Maria Teresa Turrion Borrallo's care.
Maria was hired by William and Kate back in 2014 to help care for baby Prince George when he was around eight-months-old.
Maria has been a part of the family ever since, now caring for Princess Charlotte and Prince Louis, too. Prince William had a nanny as a child with his brother Prince Harry, so the setup is familiar to him.
Prince Louis started at Lambrook school just before Her Majesty the Queen died
Kate and William's nanny attended England's prestigious Norland College in Bath, which was founded in 1892 by educational pioneer Emily Ward and is known for producing top-rate nannies – many famous and royal families hire their nannies from Norland.
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