Friends of Prince William and Kate Middleton have said the couple are “nervous” that Prince Harry’s visit to London next week could overshadow the one year anniversary of the death of Queen Elizabeth II, especially if the exiled prince stirs up controversy in interviews to publicize his new Netflix series, Heart of Invictus, and the Invictus Games themselves which start next week.

However a friend of the king said that Charles was “proud” of his son for establishing the Invictus Games, and added that headlines saying that Harry had used the series to attack his father for neglecting his mental welfare as a teenager after his mother died were exaggerations.

Sources have previously told The Daily Beast that William and Kate are “irritated” by the fact that Harry is due to make a speech at the WellChild Awards on Thursday night, the eve of the anniversary of the late monarch’s death but accept there is nothing to be done about it.

And while Charles’ camp may be keen to downplay any sense of threat, there is little doubt that the release of Harry’s new docuseries just days before the queen’s anniversary, in which he appeared to take a swipe at his father for not getting him therapy as a child after his mother died, has served as an unwelcome reminder of Harry’s ability to disrupt carefully planned royal set-pieces and the official narratives they are designed to bolster.

Some observers have also pointed out that Harry’s assertion that he was not supported after returning from a tour of duty in Afghanistan seems to contradict a claim made in a 2017 podcast with Bryony Gordon, in which he praised and thanked his brother for urging him to get therapy after returning from the conflict zone.

A friend of William and Kate’s told The Daily Beast: “Harry is going to want people to watch the show. Of course that makes them nervous because William has seen how ruthless Harry has been about betraying his family to promote his projects so far. They just won’t want the dignity of the day to be overshadowed by another outburst.”

The Prince and Princess of Wales are likely to be the focal point of attention on Friday, as the only senior royals with a scheduled engagement, although details of exactly what they will be doing have still not been released.

However it now seems likely that Harry will have media interviews running that day or the next to promote the Invictus Games, which start on Saturday 9 September in Dusseldorf, and run for a week, with Harry expected to be there for all of it and Meghan expected for the closing ceremony.

A friend of the king and queen told The Daily Beast: “Charles was always incredibly proud of Harry for setting up Invictus, and remains so. I actually think he will love the new show if he gets a chance to watch any of it. The idea that Harry has used the series to attack Charles is a total exaggeration; he hasn’t.”

Asked how they understood a passage of the film where Harry says he wasn’t given support as a child after his mother died, the friend said, “It’s a fleeting remark in five hours of TV which has been blown out of all proportion by the media. I think after what Charles has been through in the last fifty years, he’ll be able to handle it.”

(Neither Charles nor William’s office responded to a request for comment on the show, or the Invictus Games more generally.)

A former staffer, who worked for both Charles and Camilla and William and Kate and knew Harry during their working career at the palace, told The Daily Beast that Harry could hardly be blamed for the fact that he is due to speak at the WellChild Awards on Thursday evening, the eve of the anniversary of the queen’s death.

The former staffer said: “Harry has always done WellChild and he only missed it last year because the queen died on that day, so it would be a bit odd if he didn’t pay tribute to her or mention what happened last year. It’s an accident of timing, admittedly one which has worked out very nicely for Harry given he has a new show to promote.

“The issue really is what he says. I’m sure he will just say a few nice words about her, and it will be fine. But if he makes even the slightest veiled criticism of his father or brother or the institution, it will really annoy Charles and William. Charles is pushing for unity, unity, unity—so the last thing he needs is Harry being divisive.”

But, of course, Harry could do anything. At an Invictus event last year Harry enigmatically told NBC Today show anchor Hoda Kotb that when he had visited his grandmother he was “making sure” that she was “protected” and had “got the right people around her”—a comment that infuriated the family with its strange insinuation that something close to elder abuse was going on at Windsor Castle.

Of course, this is what the media latched on to, just as those few seconds of apparent criticism of Harry’s father, much as they may be dismissed by the king’s circle, have completely dominated media coverage of the new documentary.

But Invictus remains a golden opportunity for Harry to recast public perceptions of him. He can burnish the image of a hands-on philanthropist and banish the pity-party narrative that has established itself as a result of his incessant attacks on his family and complaints about his upbringing.

However, given that he is the one who made those grievances such a huge deal, particularly with his book, it seems unreasonable to expect interviewers not to ask how relations between him and his family are, and for his responses not to be the media’s pre-eminent item of interest when it comes to news coverage of him.

For Harry, next week is one of the most important in his entire post-royal career. The tight rope walk he must accomplish is to promote the Invictus Games and the Invictus documentary without it looking like he is hijacking the queen’s anniversary—or re-litigating his by now well-rehearsed arguments with his family and the institution.