At the moment she wed William Arthur Philip Louis, Katherine Middleton committed herself to a life of royal service, taking on the mantle with pride as she quickly established herself as one of the most hardworking members of the monarchy.

And in the years since, she’s barely paused for breath, only ever taking time off following the births of her three children.

This year, of course, she has seen a forced change of pace as the Princess of Wales following her shocking cancer diagnosis.

It’s with a heavy heart today that an insider has revealed that the shock and pain the couple endured when they were going through this was unthinkable.

This month, a new biography of the 42-year-old has come out and takes readers inside one of the much lesser-known moments of her life. We all think we know Catherine’s story, the “every-gal-saves-the-monarchy” plotline that we’ve come to know so well. However, one of the most devastating moments of her royal career and life saw her face her worst nightmare—not only for her but for her husband, Prince William, as well.

The year was 2012 when the Princess and the other half of her letterhead, William, had decided to visit Provence. However, unknown to them and clearly their massive security retinue, a local photographer, Valérie Suau, who regularly worked for the local newspaper, was about 1 kilometer away. They holidayed on, unaware that the storm was about to hit them. All hell would break loose within days when a nearly nude photo of Catherine was about to be published in the French tabloid magazine *Closer*.

While the Princess remained composed, once they were alone, a maelstrom of emotions must have swirled within them. Back in the UK, royal lawyers were working tirelessly to prevent further publication of the photos. However, the Waleses were in a massive bind—there was no easy way to douse the flames without making it worse.

The Prince immediately got on the phone with his father, then-Prince Charles, and her late Majesty, telling them that he was about to call in the legal hounds to go after *Closer*. The couple came down hard, launching an unparalleled legal action in a French court, even though they knew that doing so ran the risk of taking attention away from their otherwise successful bit of Queen and country flag-waving. In private, they were livid and felt isolated and violated.

A royal spokesman would later reveal that William, in a later court statement, talked about how shocking the moment was. To make the situation much more painful for William was that the images had been taken within days of the 15th anniversary of his mother Diana’s death. While the French court banned further publications of the shot, the ruling had no wider application, and the pictures would go on to be splashed all over a series of European titles.

The next year, French authorities launched formal investigations into the magazine’s publisher and others involved. It would be six long years before the final appeal was concluded, with Catherine ultimately awarded $193,000 in damages.

This year, for the most part, has been rightfully focused on getting well. Insiders tell *Heat* that for the sake of herself and her children, Catherine, who is still undergoing chemotherapy, has doubled down on her commitment to get stronger. By doing so, she is going to take a step back.

In the end, we’re told that this summer will be a restorative time for the Wales family. But now, as a new school year approaches, sources say the 42-year-old is feeling anxious about getting back to work as she continues her recovery and is keen to dip her toes back into royal life, albeit in a gentle fashion.

“It’s a bittersweet time for her,” says an insider close to the Princess, who has spent the majority of the summer with William and their kids on their private estate at Balmoral Castle, as well as at Anmer Hall, their home in Norfolk. “She always gets emotional before the children go back to school because it’s a new milestone for them and a reminder of how fast they’re growing up. But she’s also excited because she’s feeling much stronger, and with them at school, she’ll have a lot more time to focus on her work again.”