Threes a crowd? Kate Middleton, Prince Harry and Prince William can't get enough of each other
Kate's determination to help Harry, 27, find a girl comes as he's repeatedly played third wheel with her and Wills at the Olympics, not that she or Wills, 30, mind - and Kate and Harry are often seen enjoying a private joke.
While some say three's a crowd, Kate, Wills and Harry can't get enough of each other.
He's even moving in with the couple when they've finished renovating their apartment at Kensington Palace next summer.
After the engagement, Harry raved about Kate, 30, joining the family, saying: 'I always wished for a sister and now I have one.'
Since then he's been just as instrumental as Wills in helping Kate settle into Royal life, especially when Wills was away on a six-week tour-of-duty in the Falklands in February and the Duchess had no one else her age to turn to.
In another touching sign of family loyalty, we've also learnt that just days before the Royal Wedding, Harry made the ultimate promise to Wills.
A source tells us: 'Even though Wills knows that Kate has a fairly large family, he asked Harry if he'd look after Kate if anything was to happen to him.
'Harry didn't hesitate to oblige as he'll do anything for William and Kate.'
Read more about Kate Middleton and Prince Harry in Now magazine dated 20 August 2012 - out now!
SEE PICTURES Kate Middleton, Prince William and Prince Harry watch cousin Zara at the Olympics