Prince Harry banked his first set of uncle points last night as he joked about babysitting for his new nephew Prince George at the launch of a charity exhibition in London.

'When I saw him he was crying, which is just like all babies,' he told reporters at the event. 'It's fantastic to have another addition to the family. I only hope my brother knows how expensive my baby sitting charges are!'

Speaking of George, he also promised that he’d ‘make sure he has fun’, as well to ensure ‘he has a good upbringing and to keep him out of harm's way’.

‘The rest of it I'll leave to the parents,’ he quipped.

Harry was at the London Getty Images Gallery for the launch of Sentebale – Stories of Hope, a new exhibition of photography in support of the charity of the same name he founded in 2006.

The exhibition is free and runs to July 26 – though an audience with royalty is, alas, not guaranteed.

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