An onlooker says Prince Louis "looked very pleased with himself" as he kept mom Kate Middleton chasing him around the field

By Stephanie Petit and Simon Perry
July 11, 2019 01:54 PM

It’s hard to upstage Prince George and Princess Charlotte, who have become known for their adorable royal displays over the years, but little brother Prince Louis knows how to get a laugh (and melt hearts) too!

The 1-year-old royal was the “unexpected” star of the family’s outing on Wednesday to watch Prince William and Prince Harry compete in a charity polo match, an onlooker tells PEOPLE.

While his older siblings were busy kicking around a soccer ball and showing off some dance moves, Louis kept mom Kate running after him as he explored the area.

Before the polo game started, Louis was “scampering out and dashing out to the edge of the polo field, and she was running out after him and picking him up, and eventually she sat down with him at the wooden border and pointed out the horses,” according to another observer. “She took him over to the polo ponies at the polo lines and chatted to the grooms with him.”

The observer adds, “He is a funny little chap. He looked very pleased with himself.”

Max Mumby/Indigo/Getty
Prince Louis and Kate Middleton
Tim Rooke/Shutterstock
Prince Louis

Then there was the hilarious moment when Louis showed off a new look to Meghan Markle and baby cousin Archie — rocking his mom’s sunglasses!

“I’m pretty sure she was wearing them, and he put his hands out. She took them off the top of her head and the next thing is he was wearing them,” the source says.

“He had his tongue out and was waving his little hands around,” the observer adds. “He is a real character.”

Prince Louis and Kate Middleton
Max Mumby/Indigo/Getty
Prince Louis, Kate Middleton, Archie and Meghan Markle
Max Mumby/Indigo/Getty

And when it was time for a snack break, the family retreated to their car for a picnic.

“Louis had a Tupperware pots and was chewing on a freezer pack from a cool bag,” the source recalls. “[Kate] took a Tupperware tub out, and he was munching on carrot or pepper sticks.”

Kate Middleton and Prince Louis
Kate Middleton and Prince Louis
Max Mumby/Indigo/Getty

Royal fans are quickly growing accustomed to Louis’ scene-stealing moments.

In May, he showed off his adorable wobbly walk during a visit to a garden designed by Kate, then he stole the show on the palace balcony during Trooping the Colour in June with his thumb-sucking and enthusiastic royal wave.

Prince William and Prince Louis
Matt Porteous/PA
Prince Louis, Prince William and Kate Middleton
Tim Rooke/Shutterstock
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Kate recently revealed that her youngest son “is keeping us on our toes.”

“I turned around the other day and he was at the top of the slide — I had no idea!” she said during an outing in May.