A royal biographer claimed that Queen Elizabeth II cares for Prince Harry because she worries about his mental health.

Andrew Morton said the British monarch has "got a soft spot" for her youngest grandson because of his "mental struggles." He explained the extent of their closeness during an interview on ITV's "Lorraine" and said, "Courtiers will have an appointment with the Queen and it'll be three weeks hence. But he can turn up at Buckingham Palace or Windsor Castle, walk in, say hi and get the Queen to be involved in the Invictus Games."

The author of "Meghan: A Hollywood Princess" said the Queen is endeared toward the Duke of Sussex because of the struggles he had to face growing up after Princess Diana's death.

He explained, "The Queen has got a soft spot for Harry because obviously the tragic nature of his mother's death, his struggles to cope with that, his mental struggles, the fact that he's cursed with charisma in a way."

Morton shared that Prince Harry shared his mother's charisma. He admitted that when he sees the duke on royal engagements, "it's very much like watching Diana kneeling down hugging kids it's remarkable."

The 37-year-old had also admitted in his interview with the "Today" show in April that he and Queen Elizabeth II share a special bond. It is apparently very special that he could just walk in and pay her a visit at Windsor Castle.

The Duke and Duchess of Sussex had tea with Her Majesty when they dropped by to visit her ahead of their trip to the Netherlands for the Invictus Games. Talking about their visit, he said the monarch looked well and reportedly still has a great sense of humour.

It is believed that the couple kept their visit to Her Majesty a secret from palace aides so they could talk in private. They had not wanted her staff listening in on their conversation. They reportedly also had help from Princess Eugenie.

Prince Harry and Meghan Markle are expected to be in the U.K. in June with their children Archie, 3, and Lilibet, 11 months. They will join the four-day Platinum Jubilee celebrations for Queen Elizabeth II.

Meghan Markle, Prince Harry, Queen Elizabeth II
"Harry, Meghan and Archie will always be much loved family members," Queen Elizabeth stressed in her statement Photo: POOL / John Stillwell