According to the source, Prince William has always had a wandering eye, which is something Kate Middleton supposedly chose to accept when she got back together with Will after their short-lived breakup in 2007.
"He has always had a roving eye, far more so than Harry, who is meant to be the family playboy," the source told Express UK. "That’s something Kate has always known and accepted—it was part of the deal, if you like."
In April 2007, Kate and Will decided to call things off. "He is only 24 and simply wasn't ready to settle down,” said a source. The separation didn’t last long and Prince William reportedly begged Kate to take him back.
In her book Kate: The Future Queen, royal expert and biographer Katie Nicholl says that by the end of May, Will knew the breakup was a mistake and tried to win Kate back. However, Nicholl says, “She had been badly hurt and told William she needed some time."
Later in June, Will invited Kate to a costume party and followed Kate around "like a lost puppy". "Will pleaded with Kate to give their relationship another go," says Nicholl, and by the end of the night, they were back together.
And the rest is history.
Since then, the pair’s relationship has been stronger than ever. They’ve been married for eight years now, have three children - Prince George, Princess Charlotte and Prince Louis - and have found their stride as arguably the world’s most-loved royal couple.