The Duke of Sussex should "stop whingeing", keep his head down and avoid baring his soul in public in future, a royal author has warned.
Harry and the Duchess of Sussex opened up candidly about their struggles in the ITV documentary Harry & Meghan: An African Journey.
Meghan admitted to feeling vulnerable and spoke of the pressures of royal life amid intense tabloid interest, saying: "It's not enough to just survive something, that's not the point of life. You have got to thrive."
READ MORE: Prince Harry: I will protect my family but William and I are on 'different paths'
The duke, questioned about an alleged rift with the Duke of Cambridge, said he and his brother are now "on different paths" and have "good days" and "bad days" in their relationship.
He also told of the pressure he felt trying to protect his family from unwanted media attention.
But royal commentator Penny Junor called the television appearance a "huge mistake" and urged the duke to change his approach.
"My advice would be to keep his head down, and I'm afraid to say, stop whingeing," the writer said.
"It's beginning to sound like a bit of a whinge. That's not the Harry that we know and love.
"Yes, Harry's been through a lot, but there's a lot of other people who have been through a hell of a lot as well, and a lot of people who don't have the privileges that he has."
Junor added: "He does do, and can continue to do, some really good work and make a real difference to people's lives.
"He's got to get a grip on himself.
"He's got to stop feeling sorry for himself and look at the positives - shut out the criticism, just ignore it as his father has done, and get on with the work, get on with the job."
Video: Prince Harry breaks down during emotional speech at WellChild Awards
She suggested Harry should follow the Queen and the Prince of Wales's leads.
"The royal family has always in the past very successfully pursued this policy of keeping their head down and saying nothing," Junor said.
"I think that is a dignified way of dealing with problems, but it's not the American way and that's the real problem."
US-born former actress Meghan told presenter Tom Bradby she had tried to cope with the pressures of her new royal life by putting on a "stiff upper lip", but she was not prepared for the intensity of tabloid interest.
"I really tried to adopt this British sensibility of a stiff upper lip," she said. "I tried, I really tried.
"But I think what that does internally is probably really damaging," the duchess said.
Junor said: "I think it's fine if you need somebody to speak to. Maybe the Queen and Prince Charles have not internalised it.
"But their counsellor has not been the great British public via a television documentary.
"It's fine to speak to someone in private, a therapist, but don't spill your soul in public. I don't think it works."
She added: "Diana was a great one for baring her soul in public. Harry is doing exactly the same thing.
"Diana also read absolutely everything that was written about her and got profoundly depressed about it."
Junor said Harry's father Charles had his own troubles with the press, but took a very different stance.
"When I interviewed Prince Charles in the 1980s and his marriage was in trouble, he said to me that he got so angry when he read the newspapers, because they were all so full of lies and he wanted to correct each and every one," Junor revealed.
"He realised that you can't do that, so he stopped reading the newspapers and he read The Times and that was it.
"It's far better just to ignore it and just let everything go."
The royal writer said the Queen had kept her personal feelings and emotions to herself throughout her reign.
"I'm sure there are times when she has found life difficult, but we don't know that and I think she's always conducted herself with huge dignity, and the British public appreciate that," she said.
"Of course we're talking about different generations, but I think she'd probably be a little bit dismayed by what is going on at the moment."
Junor added: "I think it was a huge mistake to make this documentary in this vein."
The couple's high-profile overseas visit to Africa, carried out at the request of the Government, was overshadowed on the penultimate day when the duke launched a scathing attack on the British tabloid press, as news of Meghan's lawsuit became public.
The duchess is suing the Mail on Sunday over an alleged breach of copyright and privacy after it published a private letter between her and her estranged father.
The Mail On Sunday said it stands by its story and will be "defending this case vigorously".
Harry later filed his own proceedings at the High Court against News Group Newspapers, which owns The Sun and the now defunct News of The World, and Reach plc, which owns the Daily Mirror, in relation to the alleged illegal interception of voicemail messages.