Prince Harry "didn't hear from Charles" about his invitation to the Coronation and instead received an email from his father's office, according to a friend.
The Duke of Sussex confirmed he will be attending the historic event at Westminster Abbey, while his wife Meghan Markle remains in California with their children.
Harry is thought to have a "very tense" relationship with the Royal Family following the release of his memoir Spare.
In the book, the 38-year-old described his step-mother Queen Camilla as "dangerous" and detailed an alleged physical confrontation with his brother Prince William.
Now, a close friend of Harry's has said he didn't receive his Coronation invite the way he had hoped.
"They didn't hear from Charles. Harry wanted to hear from his father directly — it's always through somebody," the pal told People.
They added that Harry is going to the historic event as a show of support to his father, "not an institution".
"This is about a son showing up for his father rather than the optics of the institution," the friend said.
Another source told the publication the father and son eventually connected, although not in person, and had "positive conversations".
They also said it was King Charles' "first wish" for Harry to join him at his Coronation.
Meanwhile, Meghan will be staying at home with Prince Archie and Princess Lilibet, with her son celebrating his fourth birthday on the same day as the Coronation.
Confirming Harry and Meghan's decision, the Palace said in a statement: "Buckingham Palace is pleased to confirm that the Duke of Sussex will attend the Coronation Service at Westminster Abbey on 6th May.
"The Duchess of Sussex will remain in California with Prince Archie and Princess Lilibet."
Archewell, Harry and Meghan’s charitable foundation, issued a near identical statement.
A spokesperson said: "The Duke of Sussex will attend the coronation service at Westminster Abbey on May 6th. The Duchess of Sussex will remain in California with Prince Archie and Princess Lilibet."
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