Laura Dern made one final vow to her mother, Diane Ladd, before her death from lung disease. "I made a promise to my mom that I would continue to honor her legacy, and her commitment and service to teaching and advocating for other families going through an ILD," Dern, 58, told People on Wednesday, January 28, of raising awareness for idiopathic pulmonary fibrosis (IPF), a form of interstitial lung disease (ILD). IPF is a progressive lung disease that occurs "when lung tissue becomes damaged and scarred - what's known as fibrosis," per Mayo Clinic. The term idiopathic indicates the cause isn't known. Those with the irreversible disease experience stiff and damaged lung tissue, making it difficult for the lungs to perform their daily function. It is the most common form of ILD, a group of conditions that typically cause inflammation and progressive scarring of lung tissue. "She never wanted anyone to have to naively be in pain without answers," Dern continued. "Just too much time was spent like that for both of us. Every caregiver has their own experience filled with fear and frustration. Looking for answers with an irreversible disease is quite a journey." Diane Ladd's Husband Robert Charles Hunter Died 3 Months Before Her Death Dern, who is sharing details of her mom's health battle through her new awareness campaign with Boehringer Ingelheim, Beyond the Scars, joked that Ladd "demanded" her to continue to publicize the condition and help others who may be experiencing something similar. "We're talking about Diane Ladd! It was a demand," Dern quipped. "I'm privileged to be able to fulfill it and I care deeply as well, but no, it was a required want to make a difference." Ladd died on November 3, 2025, at age 89. Her cause of death was listed as chronic hypoxic respiratory failure with IDL as a contributing factor. Dern explained that it took several years for her mother to get a proper diagnosis from doctors. "People dealing with shortness of breath and coughing ... [doctors] start to want to categorize it in rather simple ways, including ending up in the hospital a couple of times with pneumonia - until finally, with a chest X-ray and seeing literally like spiderwebs in her lungs, they were able to diagnose her with IPF," the Marriage Story actress explained. "And I think that was the moment that my mother gave that same fearless, radical passion to being a self-advocate for her own living." Amy Sussman/Getty Images As Ladd's caregiver, Dern began taking her mother on walks to "distract" her and open her lungs. With those walks came unforgettable chats, eventually leading the mother-daughter duo to write the joint memoir, Honey, Baby, Mine, in 2023. The Jurassic Park actress also appeared on the Today show on Wednesday to discuss her new campaign, emphasizing how an IPF diagnosis can be "easily missed" and written off as pneumonia or another breathing condition. When Ladd was first given her "terrifying" diagnosis, doctors informed her family that she only had three to six months to live. However, the disappointing prognosis was not something Ladd ever accepted. "She was like, 'Hold on, we're not playing this game. I have a lot to do,'" Dern said of her mother's reaction to the news. "And that fire in her really inspired me as the caregiver to support her mission." Ladd ended up living six years beyond her life expectancy, time Dern and her family were grateful to get to spend with her. "She would always say, 'They told me three months, and instead of dying, I did two movies, a TV show, wrote a book with you and did my autobiography and wrote a screenplay,'" Dern recalled.