Laura Dern and Diane Ladd's 'rather shocking' family secret revealed by Ancestry

Laura Dern and her mother Diane Ladd discovered a "rather shocking" family secret after researching their ancestors and their heritage.

Dern and Ladd spoke to TODAY.com about their discovery, and how it relates to Ladd's great-grandmother, who Ladd said inspired her to leave the South and move to New York City to pursue her acting career.

"There was something secret that came out that knocked me for a loop," Ladd says, speaking about her great-grandmother Prudence, or Aunt Prudie, as Ladd called her.

The pair found out through DNA testing, genealogy records and resources from Ancestry that Aunt Prudie actually had another name that Ladd never knew: Laura Prudence Smith Ladner.

"I think we were rather shocked by what we found out in that. We realized that our experience of our origin stories are oral histories from relatives," Dern says. "And just like in any relationship, stories changed and people pepper in their version of an experience."

Dern, 56, says this was an "amazing opportunity" to "actually know where you’ve come from, or how your descendants’ journey to where they ended up, how you made it here and the mysteries of genetics."

Ladd, 88, says she "didn't have any expectations" going into the process of finding out more about their ancestors, and was able to find out more about her last name — including clearing up a rumor about it that spread at the British Academy Awards decades ago.

"My name originally was Ladner, not Ladd. Hollywood took my 'ner' away," Ladd says. "When I won the British Academy Award, they announced that I was Alan Ladd's daughter to like 72 million people. And I'm not. I've never been able to quite straighten that out."

Ladd says she found out the name originally was Lanier. When her ancestors — four brothers — came from France to the U.S., they switched their name to Ladner, she says.

Ladd and Dern started their journey of learning about their family history when Ladd was diagnosed with a lung disease in 2018 and given just three to six months to live by her doctors.

"So we started walking, because they told her I would be dead in three months," Ladd says. "That was four years ago."

While on long walks to exercise Ladd's lungs and body, Dern asked her mother to start sharing stories about her life that she hadn't told her before — at first, to distract her from the challenge.

The pair began to talk about personal topics ranging from love to ambition, and turned those conversations into a memoir, titled "Honey, Baby, Mine" and published earlier this year.

"Those walks not only gave us the benefit of more life, but the understanding of our life because of the fact that we thought that I was dying," Ladd says. "We told each other everything. People don't tell each other everything. People don't even tell each other the truth. As we wrote in the book, you have to have courage to reach out across the aisle to each other to gain peace and harmony."

Ladd added that the book has inspired readers to connect with their loved ones, and that she hopes others share their experiences of "going deeper" and finding out about their family histories.

"In the book, we had questions that came up, that amazingly had natural answers if we dug further, which we got to do," Dern says. "That's really exciting and within our own family ... it's impacted everybody."

The pair urged those who are interested in finding out about their ancestors to do it together, like they did when they revisited meaningful places in their lives across New York City for Ancestry's "unFamiliar" series.

"I have to say, as interesting as it is to learn your ancestry, to do it with a relative, when the two of us didn’t know what we would discover and to share that together, was an amazing experience in real time," Dern says. "I think it would be amazing for siblings or family members to have that as a journey together and get to discover it at the same moments because it’s an amazing thing."

Ladd adds there is no “right time” to begin learning about the past.

"If you're ready to ask the question, then get out there and be ready to get an answer. Everybody has their own clock going, and everybody's clock is different, so I think there's no need to wait if you're ready to ask the question, because you might get a wonderful answer."

Given what Ladd and Dern have gone through, the "Big Little Lies" actor cautions those to act now, while there is still time.

"Don't wait for a diagnosis to talk to each other," Dern says. "We've all heard the stories of friends losing a loved one and saying, 'I wish I'd asked' or 'I wish I told them I loved them,' and we've all gone through heartbreak with loss, where there was more to say and more to do, and maybe that's a part of life."

Dern continues: "But while we are all here, that we may communicate, tell each other how we feel, heal old wounds, talk about sharing stories."

Dern now has an "archive" for her children and their children. And to think, she says: "I just was trying to get mom walking, which was painful at the time because she was on oxygen, and it was very difficult..."

"And now I'm running!" Ladd chimes in.

She's not only just running — the 88-year-old is training for the Boston Marathon, Dern says. "That's next — that's for the next book," she says with a laugh.

This article was originally published on TODAY.com