Although Trooping the Colour is meant to mark the official birthday of the reigning monarch, it was little Prince Louis who stole the show. 

The young child smiled and greeted the crowd with excitement as he rode in a carriage along the Mall in London. Accompanied by his mother, Catherine, Princess of Wales, and his siblings, Prince George, 11, and Princess Charlotte, ten, they enjoyed the royal procession in an Ascot Landau.

Meanwhile, their father Prince William took part in the parade on horseback alongside the Duke of Edinburgh and the Princess Royal.

Taking a moment to himself while driving by a sea of Union Jacks, Prince George, who is second in line to the throne, placed his hands over his eyes.

A toothy Prince Louis reacted by mimicking his older brother’s gesture.

Cameras captured the sweet moment Prince George responded to his brother’s antics with a beaming smile as the younger, more cheeky royal threw his head back with laughter.

Before they could get up to more mischief, Catherine led the children inside to prepare for the famed flypast.

Both princes wore smart suits with white shirts and striking red ties as they took part in the historic parade which involves over 1400 soldiers, 200 horses and 400 musicians.

Taking a moment to himself, Prince George covered his eyes with his hands

Mimicking his older brother, Prince Louis also placed his hands over his eyes

George, who is second in line to the throne, burst into laughter as the younger, more mischievous royal threw his head back with joy

The Wales Family certainly seem to enjoy coordinating their outfits with Charlotte and Catherine sitting opposite the boys in the carriage wearing matching blue dresses.

Catherine, 43, looked resplendent in an aquamarine coat dress from her late mother-in-law Princess Diana’s favourite designer Catherine Walker – complete with a wide-brimmed hat by Juliette Botterill.

The mother-of-three accessorised with the Irish Guards regimental brooch as well as the Bahrain Pearl Drop earrings in a sweet tribute to the late Queen Elizabeth II.

They were crafted from pearls gifted to the Queen and Philip from the ruler of Bahrain at the time of their wedding in 1947. 

Her mini-me daughter Charlotte also paid tribute to the late monarch by rewearing the Diamond Horseshoe brooch she wore to her great-grandmother’s funeral.

The brooch, which has been in the Royal Family for generations, had been a gift from her ‘Gan-Gan’ the Queen, and was a fitting nod to Her Majesty’s love of horses.

Later on, the Royal Family appeared on the Buckingham Palace balcony for the RAF flypast.

As ever, Louis put on a cheeky display for spectators – some of whom had camped overnight in a thunderstorm for a good view of the parade.

Prince Louis is known for his cheeky antics. He is the youngest son of the Prince and Princess of Wales

The brothers wore matching suits with striking red ties

The Wales children and their mother Catherine ride along the Mall towards Horse Guards Parade on Saturday

Princess Charlotte and the Princess of Wales wore matching blue dresses for the occasion

An unrecognisable Prince William rides a horse during Trooping the Colour

The youngster, known for his ‘window wiper wave’, waved excitedly at fans as he showed off his gap-toothed grin.

Ever the composed older brother, Prince George gently tried to calm Louis down by placing one hand on his arm.

Their father William, 40, who looked handsome in a scarlet military tunic looked down affectionately at his sons.

At one point, Louis turned to his grandfather Charles and appeared to make an observation about the fighter jets flying overhead.

If Louis once found the proceedings overwhelming, you wouldn’t know it from the way he snuck in one final wave before Catherine gently ushered her brood back into Buckingham Palace after the spectacular flypast was concluded.

Commenting on the young royal’s reluctance to go back inside, Judi James told MailOnline: ‘There was a seismic change in royal body language signals on the balcony with Louis suddenly morphing into the most visible and active royal but for all the right reasons.

‘Instead of his usual playful activities, he appeared totally focused on the aircraft, only turning to his dad to show off his plane spotting skills, with the affirming nods from William suggesting his younger son is becoming a bit of an aircraft expert

‘It was also Louis lingering longer before going back in, to gaze down at the crowds and to keep up the increasingly royal looking waves longer than the rest of the Firm.’

The King, Prince of Wales and Prince Louis all wave to the cheering crowds gathered outside Buckingham Palace

The royals watch a flypast involving aircraft including the Red Arrows, Chinook helicopters and a Lancaster bomber

The young royals smile as they enjoy this year’s Trooping the Colour balcony appearance

Prince Louis and Princess Charlotte turn back towards the crowds as they leave the balcony at Buckingham Palace

The Prince and Princess of Wales share a sweet family photograph on their Instagram

Taking cues from his father and grandfather, Louis attempted different variations of his royal wave while making sure his siblings were thoroughly entertained throughout their balcony appearance – one of the most eagerly-awaited moments of the day.

But there was a more sensible side to Louis as he joined Princess Charlotte, Prince George, and Sophie, the Duchess of Edinburgh in observing one minute of silence in honour of the 241 passengers and crew killed in the Air India plane crash.

The Boeing 787 Dreamliner bound for Gatwick Airport came down in the Indian city of Ahmedabad on Thursday.

After the parade, the Prince and Princess of Wales shared a sweet family photograph on their Instagram.

‘Another brilliant day at Trooping the Colour for His Majesty’s Birthday Parade,’ the caption read. ‘Thank you to everybody who came, and to all those that took part.’