Although her husband is expected to attend, we won’t be seeing Kate Middleton at Princess Diana’s statue unveiling—and according to one report, her absence already “speaks volumes.”

Duchess Kate, 39, is skipping the ceremony in honor of the late Princess of Wales on Thursday, July 1. The memory launch, which takes place on what would have been Diana’s 60th birthday, will be attended by Prince William and his brother, Prince Harry, instead. According to one source who spoke to The New York Post’s Page Six, the Duchess of Cambridge’s reason for skipping the event with her husband and brother-in-law is “telling on so many levels.”

“Catherine’s absence speaks volumes,” the insider told Page Six in a report published on Monday, June 28. “I think keeping the numbers down is a perfect ‘excuse’ for Catherine to stay away. William is fed up with the drama and Catherine doesn’t need to be dragged into this.” The source went on to claim that Prince William, 38, and his wife are instead “planning a private family visit with their children, and that private moment is far more important than the public rhetoric.”

“It’s highly doubtful there will be a coming together of the brothers for anything more than the unveiling,” the source continued. “Harry can be petulant and defensive and is unlikely to apologize or even acknowledge any wrongdoing and William, who has seen the hurt caused by his brother ripple through the whole family, is not sanguine about how their relationship is changed for good.” The insider noted, “The gulf between them is more than the 5,000 miles between London and California.”

Duchess Kate’s absence from Princess Diana’s tribute was first reported on June 17, after Daily Telegraph associate editor Camilla Tominey revealed to Express that Buckingham Palace never suggested anyone other than Prince William and Harry would be attending the event. “We’ve never really been told that family is going to be included in this thing, we know this is the reunion for the brothers on what would have been Diana’s 60th birthday on 1st July,” Tominey told the site at the time. “Never any suggestions that the Cambridges would attend along with Prince William and equally, that Meghan and the children would attend with Harry.”

Indeed, Harry’s wife, Meghan Markle, is expected to remain at home in Montecito, California with their son Archie and newborn daughter Lilibet “Lili” Diana. William and Harry’s father, Prince Charles, is also expected to skip the event, according to a source who spoke to the UK Times on Sunday, June 27. “These moments have the potential to resurface old wounds, and it brings back memories for him; happy, sad, regretful,” the source told The Times. “Since Diana’s death, he has felt it’s best to keep those memories to himself and leave his sons to it.”

The palace has since confirmed that William and Harry will only be joined by Diana’s close family, and the artists involved in the design of her tribute statue.