Like most celebrities and members of the monarchy in the endless spotlight, Prince William and Princess Kate tried to keep the beginning of their romantic relationship under wraps.

Royal biographer Robert Jobson, in his new book, Princess Catherine, writes that the couple attended dinner parties with friends and were somewhat successful until attendees took part in the popular drinking game "Never Have I Ever."

According to Jobson, Carly Mathy Barth, one of the Prince's former girlfriends, was also in attendance and revealed that Prince William and Kate Middleton were dating during the confessional-like game.

"Perhaps unwittingly, Carly revealed Prince William and Lady Catherine's secret romantic relationship, much to the prince's chagrin," Jobson wrote in his biography.

In 2002, royal biographer Katie Nichol made the same claim in her book The Making of a Royal Romance.

"She announced that she had 'never been on a date with either of them in this room,' but because Kate was sitting next to her, she knew very well that William was the only person she had ever dated," a source at the party told the author.

In response, according to the same source, Prince William gave his ex-girlfriend a "thunderous look" and then whispered under his breath: "I can't believe you said that."

"We knew they were together, but this was the first time Prince William had publicly acknowledged his relationship with Kate," the source continued at the time.

The public revelation was shocking, but not what anyone at the time would consider "breaking news."

"It was an open secret among the student community that they were a couple," Jacobson wrote, and Prince and Princess of Wales frequently spent time together, walking to class, going grocery shopping, and listening to music at night He adds.

They first met in 2001 while studying at the University of St. Andrews in Scotland. According to a leading rumor, William "won" Middleton over at a student fashion show for charity, paying £200 to sit in the front row to watch his future bride walk the runway.

According to "The Crown" historian Robert Lacey, their first meeting and subsequent courtship was no accident.

"Kate was very strategic," Lacey said, as reported by Elle. She gave up on her offer to attend the University of Edinburgh, one of the top universities in the U.K., and chose another university that probably did not have the same academic standards."

"She had already rented an apartment in Edinburgh," he continued, "but she changed universities and changed her course to art history because it was William's college.

"She delayed her own further education for a year and even considered the possibility that she might not get into St. Andrews.

Whether by chance or calculated choice, things are apparently going well for the couple, who recently celebrated their 13th wedding anniversary.