Patti Davis' relationship with her late mother, Nancy Reagan, was rocky at times, but Davis says that watching her late father, Ronald Reagan, battle Alzheimer's prior to his death propelled her to put their differences aside.
"At some point, and really it was at the beginning of my father's illness, I chose to aim for peace of mind in and of itself with my mother," Davis said during an interview that aired on Thursday's Today show. "I made a decision to look at her and look at us through a different lens -- through a more loving, forgiving lens."
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In her 1992 memoir, The Way I See It, Davis claims Nancy hit her and criticized her for her weight. Davis told Today that she now regrets some of the things she wrote.
"I get now why I behaved the way I did and why I acted out in the way I did and wrote things that I wish I could remove from the face of the earth, but I can't," Davis said.
Part of that acting out included smoking marijuana by the age of 15, and developing an addiction to diet pills. The drug use and addiction struggle came as a shock in light of Nancy's "Just Say No" anti-drug campaign.
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Later in life, Davis found other ways to rebel. At 42, she posed for Playboy.
"People have seen me blow it. People have seen me do good work," Davis told ET on the set of the 1994 photo shoot. "It's what I was born into."
While Davis' relationship with her mom was up and down, Nancy and Ronald's relationship seemed to get stronger with time. Davis shared with Today that even as children, she and her brother, Ron, were aware of their parents' legendary bond.
"The feeling was sort of like if a band of gypsies came and took me and Ron away, they would miss us but they'd be fine," Davis said with a laugh.
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Not even Ronald's death could break the couple's bond, as Nancy once said that she would not be afraid to die and couldn't wait to be reunited with her husband.
"I'm happy for her that she is with my father now," Davis noted.
Davis will deliver the eulogy at her mother's funeral tomorrow along with her brother Ron.
More than 1,000 people have reportedly been invited to the funeral. The guest list includes heads of state and former presidents, as well as "Just Say No" advocate Mr. T, Oscar winner Anjelica Huston and journalists Katie Couric and Sam Donaldson.
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The former first lady will be laid to rest next to her late husband at the Ronald Reagan Presidential Library in Simi Valley, California.