Prince William and Kate Middleton plan to visit Princess Diana's grave at Althorp after baby arrives
Kate Middleton never met Prince Diana
Prince William and Kate Midldleton might have two baby showers
Princess Diana died when Prince William was 15
Princess Diana, who died when Wills was 15 years old, knows how excited his mum would have been about a grandchild.
The Duke and Duchess of Cambridge are planning a baby shower at Kensington Palace on Sunday 30 June - significantly, the day before what would've been Diana's birthday.
'Wills is very excited about it,' reveals our insider.
'His view is that his mum will be there with them in spirit as they look forward to the baby's arrival.'
Although guests will bring gifts for the Royal baby, Kate and Wills have told them not to go crazy spending money.
'They just want to have fun and relax before the big day,' adds the source.
Now's previously revealed how Kate's sister Pippa wanted to throw the shower at their parents' home in Bucklebury, Berks.
But Kate Middleton likes the new plan, although she hasn't ruled out doing both.
In an interview last year, Wills talked openly about wishing his mum was still around, saying: 'I'm just very sad that she never got the chance to meet Kate.'
And although he isn't especially close to his mum's brother Earl Spencer, he's told pals that he and Kate plan to make a trip to the family home in Althorp, Northants, after the baby's born to meet up with some of his maternal relatives and to visit Diana's grave.
'It'll be incredibly emotional for them,' says the pal.
'Kate's been before and was totally overcome - especially as Wills got tearful.
'He's said it'll be the proudest moment of his life when he becomes a father.
'But it'll also be tinged with sadness because his mum won't be there.'