Prince William looked out for Prince Harry during King Charles III and Princess Diana's rocky marriage. According to Russell Myers' new book William and Catherine: The Monarchy's New Era: The Inside Story, the Prince of Wales and the Duke of Sussex were extremely close in the years leading up to their parents' separation in 1992. "The brothers already shared a deep bond, with William forging the protective instincts he would display for decades," he wrote in the tell-all obtained by Marie Claire. Prince William, Princess Diana and Prince Harry in Austria in 1995.