Prince Charles has been in regular contact with Prince Harry over the past few months.
Prince Charles and Prince Harry
Earlier this year, Harry and his wife, Duchess Meghan, quit as senior members of the royal family and moved to Los Angeles but Harry's father Charles, 71, has maintained a "rock solid" relationship with Harry, even after a new biography of the couple blasted the royals.
A source told The Sun newspaper: "They have a very strong and close father-and-son relationship. Many people have speculated that the book was the end for Harry and Meghan in Britain.
"But the Prince of Wales has made it clear the door is always open. Since his move to Los Angeles they have been in regular contact. Charles is not an avid user of texts but there are video and phone calls."
'Finding Freedom', the new biography of Harry and Meghan written by royal reporters Omid Scobie and Carolyn Durand, details alleged conflicts between the couple and the royal family but insiders insist it has not affected Charles' relationship with Harry, 35.
The source added: "The book has never been a massive talking point between them and Charles is determined that it is not an obstacle.
"Their relationship is rock-solid and they remain close. They speak at least once a week and Charles is still a massive driving force in Harry's life."
Another source added that Charles is a "great sounding board" for his son.
The insider explained: "Since moving to LA, Charles has been there for Harry. They regularly discuss how he is doing and the work he is looking to embark on.
"The Prince of Wales is a great sounding board for Harry."
Charles is also close to his daughter-in-law Meghan, 39, and walked her down the aisle at her wedding to Harry in May 2018.
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