Prince William and Princess Kate Middleton are making their own rules about royal life. At least according to one royal expert, the video released to announce that the princess has completed her cancer treatment is proof of that.

In a deeply personal video released by the Prince and Princess of Wales on social media on Monday, September 9, the royal family shared intimate footage of Middleton enjoying time with family, including William and their three children Prince George, 11, Princess Charlotte, 9, and Prince Louis, 6.

Middleton also narrated the video herself, adding a personal message to the caption of her Instagram post, telling supporters that she was “relieved to finally be done with chemotherapy” and that her cancer diagnosis was “incredibly hard” for the family. She spoke candidly about how “incredibly hard” her cancer diagnosis was for her family.

“The video means, first of all, a very, very personal connection, not just in a statement,” royal family expert Richard Fitzwilliams told Us Weekly after Middleton's video went viral. 'You can also show family life, you can also get the impression of what it's like typically. Of course, that's what we see. But equally, if you listen to the words, you can see that there was a struggle for nine months. And the struggle has been tough and is still going on.

According to Fitzwilliams, the deeply personal nature of the video that Kate and William decided to share speaks well of the truly unique nature of the couple's approach to royal life.

“From a public perspective, it gave us an insight into [their] personal [lives] that we had never seen before. Because what they felt was that it's one thing to talk about what you've been through and to try to (communicate) that. And actually showing intimacy is quite another. I'm sure there are important exceptions, but I think this is an exception. I am reminded of the Queen's words, 'Rituals are crap. They make their own rules.'

For Will and Kate, it clearly involves a willingness to be more open and vulnerable to the public than successive royal families have generally been, and the way they share their recent personal news exemplifies this.

“This time, more than anything, William and I were reminded to reflect on and appreciate the simple and important things in life that many of us tend to take for granted,” Middleton wrote in the caption of the Instagram video.