The 48-year-old actress said Monday on Today that it was "a beautiful thing" to connect with Moore and her daughters, Rumer Willis, Scout Willis, and Tallulah Willis, during a new episode of Red Table Talk.
"This show in particular is very, very special," Smith said. "I actually think it is one of the cornerstone episodes for Red Table Talk because I am a child of an addict, so is Demi. I've struggled with co-dependency issues and my own addictions, so has Demi."
"Now we're talking about that parent pain that travels from parent to child. So now you have three generations -- Demi having survived her relationship with her mother and actually finding a reconciliation there, and now starting that reconciliation process with her daughters," she added.
"My mother and I have been through that whole process," the star said. "So it was a beautiful thing to be able to share in that kind of parental-child healing moment together."
Smith has been open about her past addictions to sex and alcohol. She discussed her issues on Red Table Talk in 2018, saying she has a propensity to binge and get obsessed with certain things.
"I am a binger, and I always have to watch myself and just how I can get obsessed with things," she said.
Moore, meanwhile, discusses her issues at length in her memoir, Inside Out, released in September. The book details her personal life and career, including her "addiction" to ex-husband Ashton Kutcher.
Moore's episode of Red Table Talk premieres Monday on Facebook Watch.