“William and Kate had fallen in love and were enjoying a conventional university romance, albeit one involving elaborate cover-ups and decoys.”
The royal expert added: “In a bid to keep their relationship below the radar for as long as possible, they would leave the house at different times and arrive at dinner parties separately, and made a pact never to hold hands in public.”
The royal pair’s relationship went public after they were pictured kissing on a ski trip in 2004.
However, they had a brief split after nearly five years of dating in April 2007.
During their 2010 engagement interview, William admitted: “We were both very young.
“We were both finding ourselves and such and being different characters and such.”
Kate added: “At the time, I wasn’t very happy about it. But actually, it made me a stronger person.
“You find things about yourself that maybe you hadn’t realized. I really valued that time for me.”
