Photo: Jona Frank

Laura Dern & Diane Ladd

Hearing the doctor’s words,Laura Dernfelt the walls crumbling around her.

Her mother, actress Diane Ladd, now 87, had just been diagnosed with a lung disease called idiopathic pulmonary fibrosis and was told she might have only six months to live. “The doctor told us the one thing that can help her is getting her to walk to breathe deeper,” Dern, 56, tells PEOPLE in this week’s issue.

So with Ladd on oxygen, the two began slowly walking together around Santa Monica. As they discussed everything from their own journeys as actors to the grief and heartbreaks in their lives, including Ladd’s divorce from Dern’s father, actor Bruce Dern, 86, and the death of Ladd and Bruce’s first child, their talks “grew into a profound deepening of our relationship,” says Dern.

Courtesy Diane Ladd and Laura Dern

Honey Baby Mine Photos

PEOPLE: During your walks, what were the most important things you learned about each other?

LAURA DERN: I think the quintessential part of a parent-child relationship, which really made me laugh, was that every time my mom asked me a question like ‘What’s your favorite food?’ I would answer it. And she would say, ‘That’s not your favorite food.’ So to me, one of the greatest experiences was having us both really listen.

Victoria Stevens

Laura Dern & Diane Ladd

DIANE LADD: As parents we do not tell our children all of our truths because we want to be loved and respected. So honestly, we lie a little. What I discovered is that there were things I hadn’t told her that I should have because I felt it would make her feel guilty or burdened. Instead, it was a release for her.

LADD: I thought I was dying, so Laura and I just told each other everything. Just fixing ourselves and our relationship was a darn good beginning.

What was the hardest conversation to have?

DERN: I think asking Mom about my sister [who died at age 18 months after a drowning accident] and not wanting to hurt but only heal. And then talking about it was an amazing experience. It changed our relationship in the feeling that we can talk about everything now.

Bruce Dern, Laura Dern and Diane Ladd

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Laura, what do you find most beautiful about your mom?

DERN: She has the most open, honest face. You know what she’s feeling. It’s an amazing thing to have as a gift because I always knew I was loved. Even when it was a ferocious face or an angry face, it was so full and told so many stories that I always felt the love coming from her.

Laura Dern & Diane Ladd - Honey, Baby, Mine book jacket

Diane, when were you most proud of Laura?

LADD: When she birthed my grandchildren and I was allowed to hold that child which she brought into this earth in my arms. It makes me tear up to think about it. The greatest treasures are when our child gives us children or they give you a child in the art they choose. Those moments are the proudest that I could possibly be.

source: people.com