As Princess Diana knew the responsibility Prince William had to carry when he would become the next king of United Kingdom, she was afraid that he couldn't have a comfortable royal life. Thanks to Kate Middleton, she made everything for the Duke of Cambridge easier, helping him to find the happiness that the late Princess of Wales didn't experience.

The Cambridges are enjoying a happy marriage. They are now blessed with three kids, Prince George, Princess Charlotte, and Prince Louis. But opposite of their strong bond and the blissful union is what the People's Princess and Prince Charles never experienced.

Princess Diana and the Duke of Cornwall's fairytale love story, sadly, ended in divorce in 1996. Since then, she had a hard time to continue her royal life. Hence, according to veteran royal editor Robert Jobson's 2006 book, William's Princess, it revealed Diana feared for her son to experience the same problems she encountered.

Fortunately, as Express noted, Kate Middleton has been an important part of Prince William's life for helping him settle into his royal role. "William is a young man on the cusp of embracing public life and, hopefully, securing private happiness," Jobson wrote. "He knows that his duty makes his life a sort of sacrifice to the state, but has over the past decade or so shown that he is not one to completely submerge his personal needs and wants as a result."

With the Duchess of Cambridge by her side, the future king finds the right balance in life that Prince Charles and Princess Diana failed to have. With his wife, he found a girl who could understand his character and oppose the demands of his being a prince.

Kate Middleton makes sure that Prince William remains to have a normal lifestyle. Hence, Jobson believed that the father-of-three found a "sensible and attractive girl" in his wife, who only demands very little of him.

Prince William proposed to Kate Middleton in 2010, using the ring that Prince Charles and Princess Diana marked their marriage with. According to the South China Morning Post, the engagement ring from Garrard has been widely imitated due to the noise that comes with their relationship.

However, some questioned why Princess Diana's ring was passed on to Prince William and not to Prince Harry. Allegedly, William got his mother's Cartier Tank watch when they had the chance to get some of Diana's belongings after her death in 1997. At the time, the Duke of Sussex got the famed 12-ct sapphire and diamond number engagement ring.

However, when Prince William was ready to propose to Kate Middleton, he asked his brother for a trade. As Prince Harry was also fond of his then-soon-to-be sister-in-law, he agreed and got the Cartier Tank watch instead, which Meghan Markle now wears.