Well, what's an average Brit to say to that? "Er, gosh, right, you should really get therapy for that"? "You have the advantage over me - I didn't know her personally"?
I can't remember what I did say. But I've been reminded of what he said many times over the last few days. The papers have been full of the 10th anniversary of Diana's death, and in particular the memorial service which is being held tomorrow. It was organised by her sons - two people who have every right to miss her. They invited members of their family, people who knew her, people who will support them, and because of who she was and who they are, they were also obliged to invite some political bigwigs.
At the weekend, the newspapers reported that some publicity-seeking nobody who had never met the princess had written to Clarence House demanding that the Duchess of Cornwall be removed from the guest list. The Duchess had been personally invited by Diana's sons, who wanted her there to support them. Under pressure from the public, she has now decided not to attend.
The butler who betrayed Diana by selling stories which he had promised to keep private and has cashed in on her memory time and time again has also been in contact with Clarence House, complaining that he has not been invited. Being a shameless self-publicist, of course, he has also been in touch with all the national newspapers.
In all the public whinging about how the public is being excluded from the private memorial service on the anniversary of the day she died, people seem to forget that the princes also personally organised a massive public concert earlier this summer to enable the public to join in an event to commemorate her.
I watched the funeral, and it was a historic occasion. But this was the only image that made me cry - a picture of the flowers placed on her coffin by her 12-year-old son Harry, with the single word 'Mummy' on the card. It still chokes me up, and anyone who thinks they "really miss" Princess Diana should remember this image. To the world, she was a princess - but to that little boy, she was the world, and he and his brother should have the final say in how she is commemorated.
She was a human being. Her sons loved her. That's what's important on this anniversary of her death. I won't be amongst the crowds of people who never met her but want to gather in London to show how much they "miss" her.
But I will say a prayer for two boys who had to grow up without their mother.