Princess Charlotte and Prince Louis' interaction on the balcony of Buckingham Palace during this month's Trooping the Colour celebrations delighted fans who spotted the moment the royal siblings appeared to bump heads during the annual aerial flypast.
The royal kids made their traditional balcony appearance on June 17 marking King Charles III's first Trooping the Colour as sovereign. The military event is staged each year to mark the monarch's official birthday in June, comprising a review of troops, a carriage procession of the royal family through London and a Royal Air Force flypast.
Prince William and Kate Middleton's three children have attended sections of the event since they were babies, and the siblings made their carriage procession debut in 2022.

After riding to and from Horse Guards Parade from Buckingham Palace with Kate and Queen Camilla, the kids joined their father and other working royals on the balcony as planes were making their flight overhead. One eagle-eyed fan spotted Charlotte and Louis accidentally bumping heads while watching the festivities, then pretending as if nothing happened.
TikTok user @l0velycatherine uploaded news footage to the video-sharing platform on June 18 and captioned it: "Charlotte decided to keep it to herself."
In the clip, the princess leans in to seemingly say something to her younger brother, but at the last second, Louis, 5, turns his head and accidentally knocks her right on the noggin. Poor Charlotte winces and rubs her head but decides to continue watching the event rather than react.
@l0velycatherine Charlotte decided to keep it to herself 😠| #princesscharlotte #princelouis #princewilliam #princesscatherine #princegeorge #katemiddleton #fyp #l0velycatherine ♬ original sound - Ian Asher
The video has been viewed over 1.7 million times on the social media platform and received in excess of 93,000 likes and 300 comments. A number of TikTok users praised 8-year-old Charlotte for keeping her composure in front of the thousands of people who gathered at The Mall to watch the event.
"She's so mature, at her age I would be throwing tantrum," one person commented.
"That little Louis," wrote another user, adding a laughing emoji, with a further commenter saying: "You can tell she is growing up, so much more aware of being watched by others. She did well. That hurts!"
Prince Louis was the focus of much attention during the balcony appearance as the prince's uninhibited reactions during the royal flypasts have circulated many times on social media in years past.
In 2022, the young prince was spotted animatedly chatting to his great-grandmother, Queen Elizabeth II, during her Jubilee Trooping the Colour appearance, then covering his ears as the planes flew overhead.
This year, the prince offered the flypast his best military salute, a moving moment which some social media users compared to Prince William's similar childhood gesture over three decades earlier, while on the palace balcony with Princess Diana and his royal cousins.
James Crawford-Smith is Newsweek's royal reporter based in London. You can find him on Twitter at @jrcrawfordsmith and read his stories on Newsweek's The Royals Facebook page.
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