Princess Diana and her former marriage to then-Prince Charles became infamous for the way it ended—with Diana stepping away from the royal family after a divorce that stemmed from the now reigning monarch’s affair with Camilla Parker-Bowles. While King Charles and Queen Camilla have managed to have a happy marriage, a royal expert reports that he’s instructed his son Prince William to do better in his marriage to Kate Middleton.

“[His father] said, ‘Look, William, there’s nothing more important than your family,’” royal expert Ingrid Seward, said, speaking to Fox News. “’Don’t make the mistakes that I made,’” she added. “I just did duty, duty, duty. I neglected my marriage, and look what happened.’”

Diana felt anguished by the lack of love in her and Charles’s marriage and by his affair with Camilla. Diana would often confide in her dance teacher, Anne Allen, who revealed the details of their conversations in an excerpt from her memoir shared with People. “Why does he not love me? I really don’t understand,” she reportedly told her dance teacher. “I have tried everything, tried to conform to his wishes even though I don’t always agree. There’s no affection between us, and I am always on my own. I just want to be loved. I can’t keep going on like this. They are really expecting me to just say nothing and keep going. How do I do that?”

Seward, however, believes that William and Middleton’s marriage is very different that Charles and Diana’s, especially as the Princess of Wales battled cancer this year. “I think she’s had fantastic support from Prince William,” Seward told Fox. “He publicly said it’s been the toughest year that he’s ever had, and it’s been very … difficult. So, we can only imagine how difficult it [really] must have been because William also [had] to reassure their three young children that mummy’s going to be OK. Kids get very worried when they see their parents unwell, especially for such a length of time.”

“I think it’s been very tough, and he has been an enormous support,” the royal expert added. “And, in turn, he has been supported by his father.”