Princess Diana's Former Lover: If Charles Hadn't Cheated, Diana Wouldn't Have

Princess Diana's former lover, James Hewitt, sat down with ET's Chris Jacobs and revealed his thoughts on how Diana would have felt about the royal wedding, Charles and Diana's infidelity and the rumors he is Prince Harry's father.

Hewitt, a former officer of the British Household Cavalry said that the late Princess of Wales would have been "very proud and bubbly and jumping about on Friday – if she were here – and she would be very supportive, loving and proud. And she would probably put a joke in somewhere – a practical joke certainly."

Hewitt also dished on Princess Diana's own marriage, saying, "If Charles hadn't cheated, Diana wouldn't have."

Hewitt and Diana's affair lasted five years, sparking rumors that he is Prince Harry's biological father. Hewitt set the record straight, revealing that the affair didn't start until after Prince Harry's birth.

Click to watch James as he tackles the tough questions, and clears the swirling rumors.