Prince William will reportedly be concerned as Prince Harry "appears to be exploiting his mother's iconic status" after he used a photo of the late Princess Diana to help launch the website for his non-profit Archewell.
The new Archewell website, which Harry created with wife Meghan Markle, features a 1986 photo of the young prince sitting on the shoulders of Princess Diana.
In an introductory letter, Harry is introduced as "my mother's son" with the couple saying they have experienced compassion and kindness "from our mothers and strangers alike".
However, there was no reference made to Prince Charles or his brother Prince William, which royal expert Phil Dampier says will not go unnoticed by the royal family.
The full letter from Harry and Meghan reads:
"I am my mother's son. And I am our son's mother. Together we bring you Archewell.
"We believe in the best of humanity. Because we have seen the best of humanity. We have experienced compassion and kindness, From our mothers and strangers alike.
"In the face of fear, struggle and pain, it can be easy to lose sight of this.
"Together, we can choose courage, healing, and connection. Together, we can choose to put compassion in action."
It ends, "We invite you to join us. As we work to build a better world, One act of compassion at a time."
"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," Mr Dampier told Daily Mail.
"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.
"And although Harry has praised his father in the past, it seems odd not to mention him more and work in conjunction with him, rather than separately."
Mr Dampier added he believes Harry only focused on his mother because Meghan is so close to her own mother and estranged from her father.
"I think that for many years Harry bottled up his feelings about his mother's tragic death and Meghan encouraged him to dig deep and bring out some of the problems that he has been wrestling with," he said.
"I think that was a good thing to start with and helped him to know himself better and recover from the demons he'd been wrestling with for many years. But there is a danger that he could become obsessed with his mother's memory and fail to live in the present."
The royal expert also added that the brothers will be together during the UK summer to unveil a statue to mark Princess Diana's 60th birthday at Kensington Palace.
Mr Dampier said that while the brothers will likely put on a united front, it will take some time to repair their relationship.
He added that the Queen will "always leave the door open" for Harry to return to the royal family, but has made it clear the couple can't be half in and half out.
The claims come after Harry and Meghan's first Spotify podcast was released with their son Archie, 19 months, making his broadcast debut.
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