It's taken two decades for Prince William to process his mother's death, and now that he has, he is talking openly about Princess Diana and the effect her death had on his life.

He said he wishes she could have been around to meet his wife, Catherine, the Duchess of Cambridge, and watch his two children grow up.

Prince William offered up his rawest emotions yet on the topic of his mother's death in a cover story for GQ. He said his grieving process after Princess Diana was killed in a car accident in 1997, when he was 15, was different from other people's because "everyone [knew] the story."

Alastair Campbell, author and former communications chief for Tony Blair, conducted what turned into an emotional interview.

“It has taken me almost 20 years to get to that stage,” Prince Williams said. “I still find it difficult now because at the time it was so raw. And also, it is not like most people’s grief because everyone else knows about it, everyone knows the story, everyone knows her.”

He added: “I would like to have had her advice. I would love her to have met Catherine and to have seen the children grow up. It makes me sad that she won’t, that they will never know her.”

Prince William, 34, talked about the strength he derives from his own close-knit family: his wife; his young son, George; and his daughter, Charlotte. He also said he strives to raise his kids as normally as possible, not “behind palace walls.”

“I could not do my job without the stability of the family,” he said. “Stability at home is so important to me. I want to bring up my children in a happy, stable, secure world, and that is so important to both of us as parents.”

He added: "I want George to grow up in a real, living environment. I don’t want him growing up behind palace walls; he has to be out there. I will fight for them to have a normal life.”

The shock of Diana’s death remains real, Prince William said.

“The shock is the biggest thing, and I still feel it 20 years later about my mother,” he said. “People think shock can’t last that long, but it does. It’s such an unbelievably big moment in your life, and it never leaves you. You just learn to deal with it.”