The ugly and toxic marriage of Prince Charles and Princess Diana affected Prince William more than they ever realized.

Although Prince Charles and Princess Diana's wedding was considered as the "Wedding of the Century," it still became infamous due to its twists and turns, most especially due to the Prince of Wales' infidelity.

Because of this, their sons Prince William and Prince Harry, never really got the chance to experience a stable and happy family. However, the Duke of Cambridge -- being the eldest and most sensitive son -- got affected the most as his father's action ultimately ruined him.

According to royal expert Sarah Bradford, Prince William's parents' relationship caused instability in his life, and only Kate Middleton, Duchess of Cambridge, was able to fix that.

"I think that Kate's influence on William has been very, very important," Bradford said during the 2017 ITV documentary, "Kate: The Making of a Modern Queen." "I think he was quite seriously affected by the bad relationship of his parents, and I think that Kate has strengthened him."

Compared to Prince Harry, who has been vocal about his struggles when their mother died, Prince William is way more affected. The fact that he cannot speak about it adds more weight to his feelings.

To recall, though he was young and suffering, the 14-year-old Prince William helped his mother survive the tormenting events with Prince charles by leaving loving words to her.

The narrator of "Prince William: Royalty in My Family" claimed that the Duke wanted to end Princess Diana's suffering as soon as possible. However, a speedy divorce meant Princess Diana would need to give up her royal title.

"You'll still be mummy," Prince William said, trying to comfort his mother.

The Duke of Cambridge protected the royal princess until she tragically passed away when she got into a car accident in Paris a year after her divorce with Prince Charles. Princess Diana was together with her then-partner Dodi Fayed and driver, Henri Paul.

How Kate Helped Him

The Duchess of Cambridge's commitment to the royal family and her family-of-five helped Prince William realize that he can survive and do his royal duties together with his wife.

"Don't be under the illusion that she's a wallflower, because she's not," royal expert Katie Nicholl said in the same documentary. "She's very strong, she's very confident and she has a real clarity of vision and I think William depends on that hugely ‒ so she's brought a huge amount to William's life."

Nicholl added that the Duchess has given the Cambridge Duke the family life that he always wanted, and everything is making him incredibly happy now.

Aside from giving him the happy family which he never experienced, Kate also helped Prince William settle in his successful role now.

Veteran royal editor Robert Jobson wrote in his 2006 book "William's Princess" how the duo was able to navigate their royal lives together.

"In Kate, William has found a sensible and attractive girl who, in emotional terms, demands very little of him. For a boy who has lived through the heat of the War of the Waleses, that must seem like bliss," Mr. Jobson went on.

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