Sir David Attenborough has given Prince George a one-of-a-kind gift.
The Duke and Duchess of Cambridge and their three children George, Charlotte and Louis met with Attenborough for an outdoor screening of his new feature film, writes the Sun.
The royals' official Twitter account shared snaps of the meeting, during with Attenborough gave George a 23 million-year-old shark tooth.
But he had a serious message for the young royals as he sat next to Prince William during the screening.
The film, A Life On Our Planet, reveals what measures we should take to reverse environmental disaster.
Attenborough brought the shark tooth with him to meet William, Kate, and their children at Kensington Palace last week.
He'd found the tooth, which belonged to an extinct 15 metre-long carcharocles megalodon shark, while on holiday in the 1960s in Malta.
Earlier this year, William and Attenborough announced the Earthshot Prize, an award for anyone solving environmental problems.
His new doco A Life On Our Planet is a look back at his career.
Last week Attenborough finally got Instagram - and he hit one million followers in record time, in just four hours and 44 minutes.