Prior to their marriage, Prince William, who was dating Kate Middleton, was adamant about protecting her privacy. However, it appears he took his goal too far and hurt her feelings in the process.

In the book, “Kate: The Future Queen,” royal biographer Katie Nicholl revealed Prince William’s 21st birthday celebration was a difficult time for Kate. The gathering made the future Duchess of Cambridge doubt the Prince of Wales’ commitment to their relationship.

At the party, William had Kate seated far away from his table but arranged for his friend and rumored ex-girlfriend, Jecca Craig to be given a seat of honor.

“Kate didn’t know whether they had been romantically involved or not, but she noted that Jecca had been seated at the head table next to William, whereas Kate had to raise her glass to toast the prince from afar,” Nicholl wrote.

Although Kate was aware Prince William was trying to protect her privacy, the incident still hurt her feelings. Prior to the party, the Duke of Cambridge told the press he was single and often struggled to maintain a relationship.

“There’s been a lot of speculation about every single girl I am with, and it does irritate me after a while, more so because it is a complete pain for the girls,’ he explained.

William revealed it was important that the girl he chooses to date is able to live her life without being followed by the paparazzi.

“If I fancy a girl and she fancies me back, which is rare, I ask her out. But at the same time, I don't want to put them in an awkward situation because a lot of people don't know what comes with knowing me, for one—and secondly, if they were my girlfriend, the excitement it would probably cause.”

Years later Prince William married Kate, and the two are now parents to Prince George, Princess Charlotte and Prince Louis.

Prince William and Kate Middleton Prince William and Kate Middleton are pictured as they arrive to officially open Dundee’s V&A (Victoria and Albert) museum on Jan. 29, 2019 in Dundee, eastern Scotland. Photo: Neil Hanna/AFP/Getty Images