Kate Middleton subtly stopped Prince Louis from sucking his thumb on the royal balcony during the RAF flypast on Thursday.
MORE: Royal thumbsuckers!
Taking in the impressive RAF Voyager and Typhoon planes, the mum-of-three spotted little Louis sucking his thumb. In a bid to stop the youngster, Kate skilfully patted his head before then tenderly brushing his hand away from his mouth.
WATCH: Kate Middleton stops Louis from sucking his thumb
This isn't the first time the Duchess of Cambridge has intervened with her youngest. During the 2019 Trooping the Colour parade, Kate similarly had to step in to gently stop the young tot from sucking his thumb.
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Thursday's events marked the youngster's second Trooping the Colour and Prince Louis evidently hasn't quite mastered the rules of royal etiquette. The four-year-old pulled a variety of cheeky faces throughout the afternoon which nearly had him stealing the limelight. Dressed in his adorable sailor-style top, the young tot went viral with his comedic poses.
The four-year-old was seemingly distracted
In a further display of exuberance, Prince Louis was spotted waving over-enthusiastically during their carriage debut as they made their way towards Buckingham Palace. In a sweet brother-sister moment, Princess Charlotte chuckled before stepping in to stop her younger brother from waving.
Whilst the Queen appeared to enjoy yesterday's festivities, it was announced last night that the head of state would be missing the national service of thanksgiving at St Paul's Cathedral.
Prince Louis looked adorable in his sailor suit
In a statement, Buckingham Palace said the Queen “greatly enjoyed” her Trooping birthday parade, but taking into account the journey and activity required to participate, she had reluctantly decided not to attend the service the next day.
The Jubilee celebrations will continue on Saturday with the BBC's Party at the Palace which will entertain a live crowd of 22,000 people. The star-studded line-up includes the likes of Diana Ross, Alicia Keys, Nile Rodgers, Andrea Bocelli and Duran Duran.
The show will moreover feature appearances from Sir David Attenborough, Emma Raducanu, David Beckham, Stephen Fry and Dame Julie Andrews.
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