Prince Harry was Prince William's best man at his Royal Wedding

Royal biographer Penny Junor says Prince William and younger brother Prince Harry have a very special relationship.

Penny's book Prince William:
Born To Be King
is out now and it's clear Wills and Harry, 28, have a deep bond.

'[William] a very interesting character,' says Penny, 62.

'But there is quite a lot of Harry in my William book because it's hard to talk about them separately - they are so close and so dependent on one another.'

Penny reveals that Wills, 29, agreed to be interviewed when he found out she was writing about him - but he changed his mind.

'He hates talking about himself,' says Penny.

'However, he did allow senior members of his household to speak with me.'

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Nicola Coe