Britain's Duchess Catherine took Prince George to the Princess Diana memorial playground last week.
The duchess was seen playing in the beach section of the facility - which was erected in honour of her husband Prince William's late mother - at Kensington Gardens and the pair had a great time in the sand.
A source told the Daily Express newspaper: "It was lovely seeing them play together in the sand.They stayed for about 15 minutes.
"They had three protection officers with them but Catherine seemed oblivious to anyone except her gorgeous baby enjoying himself."
The space was unveiled three years after Diana's death in a Paris car crash in 1997 and is situated a short walk from the Kensington Palace apartment Catherine shares with her husband, George's father, Prince William.
As well as enjoying the sand, Catherine - who was known as Kate Middleton before her marriage - recently revealed George loves swimming and enjoys "grabbing things to splash with".
Swimming champion James Hickman revealed: "[Catherine] was at the [Commonwealth Games] swimming [event] last night, so I was just interested to know if she had taken George swimming.
"Hopefully if they can get him swimming he could be a future international swimmer.
"She's been swimming with him. She said he loves the water and he grabs things to splash with.
"So, maybe he could be the next royal to take part in the Olympics and if he was in swimming that would be incredible."