Prince Harry and Prince William in 2018. Photo / Getty Images
"I think William will be slightly worried if Harry uses Diana for any of his charitable or commercial ventures without consulting him, and I don't think he would be happy if Harry appears to be exploiting his mother's iconic status," he said.
"It's also very significant that Harry called himself his 'mother's son' but has made no mention of Prince Charles. William is very much following now in his father's footsteps with his environmental and conservation work."
However, he also claims it is possible Harry only left his father out because Meghan is estranged from her father Thomas Markle.
"I suspect that part of the reason for the emphasis on mothers is that Meghan is so close to her mother and of course is estranged from her father, so perhaps Harry is thinking of her when he concentrates only on Diana," the expert said.
The expert has also previously said that the rift between the two brothers does not appear to be getting better but expects them to "put on a united front" for the unveiling of Diana's statue and the birthday celebrations.
"But behind the scenes I think there's going to be a lot of tension," he told The Sun.
"I think the most interesting thing to see will be whether Meghan comes over for any of these things," he said, referring to the royal events planned for 2021. "I'm sure Harry will but it wouldn't surprise me if she doesn't come over at all."
