Kate Middleton was compelled to give a firm command to Prince Louis on the royal balcony, a lip reader has claimed.

The senior royals made an appearance in front of Buckingham Palace this afternoon to greet the thousands who had congregated on the Mall. They were marking Trooping the Colour – King Charles' official birthday.

The Duchess of Cambridge was accompanied by her husband Prince William and their three children – Prince George, Princess Charlotte and Louis.

Charles and Queen Camilla were also spotted greeting the crowds, with Princess Anne and Sophie Wessex also present.

However, as is often the case, seven-year-old Louis became the centre of attention, flashing his toothless grin at the crowd and gazing in wonder at the planes flying overhead.

As the flypast concluded and the national anthem began, cameras captured Kate seemingly reminding Louis of his responsibility. Lip reader Jeremy Freeman interpreted her words as: "National anthem, Louis stand."

It is traditional for all royals below King Charles, as well as members of the public, to stand when the national anthem is played.

Beside her, William was seen engaging in conversation with his father Charles. According to Jeremy, an elated William told him: "Oh my word, what a day."

Kate instructing Louis
Kate seen instructing Prince Louis to stand

The King responded: "Great theatre." This wasn't the only intriguing conversation Jeremy picked up during the iconic London event.

As they journeyed from Buckingham Palace to Horse Guards parade this morning, Charles and Camilla appeared to be in a heated discussion.

Jeremy interpreted King Charles' remarks, suggesting that His Majesty started with: "Absolutely crazy, disgrace, absolutely extraordinary."

The lip reader couldn't ascertain the full discussion but managed to catch parts where the King said "on my way out" which was followed by: "Meanwhile, not like me. That's the difference between me and him."

The identity of "him" remains uncertain, though fellow lip reader Nicola Hickling told the Express that the King seemed to have been referring to Prince Harry earlier on.

This year's Trooping the Colour deviated from its customary proceedings due to the recent tragic Air India plane disaster, with 241 fatalities.

Honouring King Charles' wishes, the royals donned black armbands as a tribute, alongside observing a one-minute silence to remember those who perished.

The ceremony saw over a thousand British Army members march in full regalia, echoing Britain's strong military tradition.

Central to the event was the "Colour", or regimental flag, which historically served as a rallying point on the battlefield.

Maintaining time-honoured traditions, Charles performed the ceremonial roll call, honouring centuries of historical protocol.