Princess Diana and Prince Charles’ marriage was reportedly over long before their official separation. The two are pictured leaving Westminster Abbey in London on Feb. 28, 1982.  Fox Photos/Hulton Archive/Getty Images

They may have separated in 1992 and finalized their divorce in 1996, but Princess Diana and Prince Charles’ marriage reportedly ended long before then according to a documentary.

In the documentary, “Princess Diana’s Wicked Stepmother,” Princess Diana’s former butler Paul Burrell revealed that her marriage to Prince Charles actually came to an end years before the public knew it was over—in 1984, following Prince Harry’s birth.

“I could see the cracks in the marriage between Charles and Diana getting wider and wider, Diana confided in me that on the night Harry was born, she cried herself to sleep,” he said. “She says ‘I knew my marriage was over’ and the Prince told the Princess that his duty was now done. He had provided the country with an heir and a spare and he could now resume his relationship with Ms. Parker-Bowles.”

However, Princess Diana’s upbringing is also allegedly to blame when it comes to the marriage, with royal biographer Penny Junor stating that “she was just bitterly unhappy, she was disappointed in her marriage as was Charles. It was a car crash from the very beginning.”

Junor added that the frosty relationship Diana had with her stepmother, Raine Spencer, also played a role, as the happy personality she presented to everyone was false because of that.

“When Charles and Diana got together it seemed on paper that this was the most perfect match, but Diana’s childhood had been very difficult and the happy jolly-go-lucky venire that she presented to the world was nothing more than a venire,” Junor said. “Charles was a very complex character and the two of them was about the worst match you could possibly have made.”