As he watched the Platinum Jubilee Pageant, Prince Louis displayed some decidedly unregal behavior.

A video of the 4-year-old placing his hand over his mother's mouth went viral on social media.

The boisterous lad made a series of faces, poked his tongue out, and put his thumb to his nose while wiggling his remaining fingers.

Seeing Louis standing on his chair and throwing a cushion, Kate decided to take a break with her youngest.

Prince William's cousin, Mike Tindall, noticed Louis' behavior.

In addition, he gave his mum a big hug and spent some time on his grandfather's lap.

During the Trooping the Colour ceremony on Thursday, Louis stole the show with a powerful salute.

When the royal family gathered to wave, he barreled past 96-year-old great-grandmother for a prime viewing position.

He was photographed making an array of animated faces, including a scream, hands over his ears, and eyes closed.

Camilla Parker-Bowles did attend the Platinum Jubilee Pageant, but this time Mum wasn't taking chances.

The Duchess reined in her son, who resembles her late father, Michael Middleton.