During one moment of the parade, Kate was seen subtly scolding her daughter who felt compelled to intervene when four-year-old Louis was waving a little too animatedly.
WATCH: Kate Middleton scolds Princess Charlotte at Platinum Jubilee
In the clip from Sunday's events, Kate was seen saying: "Charlotte, yes I know." Louis had also tried to casually lie back and put his feet up on Charlotte's lap, however, the young Princess was unimpressed and shoved Louis' leg off of her.
Little Louis had made headlines for pulling a series of faces. He was even spotted covering his mum Kate's mouth when he sat in the royal box - much to the world's amusement.
After delighting royal watchers, Prince Louis instantly became a social media hit. On Monday, his parents, Prince William and Kate even addressed their son's cheeky behaviour in a special Instagram post.
Kate was busy looking after her children during the parade
Sharing a series of their highlights, the royal couple said: "What a fantastic weekend of celebrations. Seeing people across the nation coming together with family, friends and loved ones has been extremely special.
"Thank you to everyone who turned out to show their gratitude to The Queen and her inspiring 70 years of leadership. From the crowds on the Mall to communities hosting street parties up and down the country, we hope you had a weekend to remember."
Referring to little Louis, Prince William and Kate ended their personal message with: "We all had an incredible time, especially Louis… [eyes emoji]. W & C."
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