Princess Diana and Prince Charles may have known that their marriage wouldn't work even on their wedding day.

The Prince and late Princess of Wales had a fairytale wedding. However, unlike the wedding itself, their marriage was far from perfect. In fact, Prince Charles and Princess Diana ended up in divorce.

According to body language expert Judi James, the couple was showing signs of anticipation for their marriage to shamble. It's easy to perceive their actions as "signs of shyness and nerves prompted by love" but it's actually not.

"It is easy to look at the body language signals of Charles and Diana on their wedding day and see, via the filter of retrospective knowledge, the signs of the marriage shambles that was to come," James told Express. "We thought this crusty bachelor – who had waited so long before finding his bride – and the young, shy nursery girl he had chosen were deeply in love and in it for life."

According to James, Prince Charles "steepled brows" as he waited for his bride was an expression of "duty' and he looked "like one of quiet suffering."

On the other hand, Princess Diana flipped from being "warm and loving to slightly sullen."

On the other hand, Dr. Peter Collett believed that Prince Charles was already showing distressed signals since their engagement announcement. The Prince of Wales was reportedly showing signs of their rocky relationship.

"When Prince Charles and Diana announced their engagement there were already signs that all was not well," Collett said. "We can see that they together, but they are not in step and Charles is not adapting his behaviour to include Diana."

"In fact, if we apply the cut-out principle, and remove Diana from the scene, it does not look like anyone is missing," the expert added.

On their big day, Collett also noticed how unhappy the future king was. There was a time Prince Charles wiped away his imaginary tears which suggests that he was "having deep regrets about what he has got himself into."

It is believed that Prince Charles has always been in love with Camilla Parker Bowles. In fact, Queen Elizabeth II and Prince Philip blamed their own son for his failed marriage with Princess Diana.

"If anything, I believe, that she [Queen] and her husband Prince Philip put more of the blame on Prince Charles, and Prince Charles of course, as we since discovered, was already committed emotionally to another woman," biographer Robert Lacey explained.