Duchess Kate was perhaps the most surprising absence from this week's Princess Diana statue unveiling.

The Duchess was initially expected to attend, but she was ultimately left off the guest list, and Prince William and Prince Harry revealed the statue with no other Royal Family members present. Now, a new report has revealed why Kate wasn't there.

Why Duchess Kate didn't attend Princess Diana statue unveiling

On Thursday, a source told Us Weekly that Kate "really wanted to attend" the unveiling that day, but the Royal Family collectively "decided it was best for the kids and her to stay home."

The reason? The source explained: "Out of respect for Harry and William, [the royal family] wanted it to be just about Diana's sons and not a huge public affair."

Prince William And Prince Harry Reveal Princess Diana Statue

So, it sounds as though the unending drama between the brothers influenced the decision. It's a sad reality, given that Kate apparently hoped to support her husband and honour the memory of her late mother-in-law Diana.

Throughout the lead-up to the statue unveiling, reports had suggested the Duchess would act as "peacemaker" between her husband and his brother. Had she been present, there may have been more focus on how they were interacting rather than the tribute to Diana.

Prince William and Harry unveiled statue without Duchess Kate

Previously, a source also told Page Six that they believe Prince William had his wife not attend because he is "fed up with the drama" and didn't want her "dragged into this."

Prince William and Prince Harry after revealing Princess Diana statue.

But, despite the ongoing feud and Kate's absence, Prince William and Prince Harry did unveil the statue on Thursday without incident, as was expected.

The brothers walked side by side to the statue and together removed its cover. They chatted briefly, and Harry appeared especially cheery while William looked more reserved as they honoured what would've been their mother's 60th birthday.