Williams once took to the streets of San Francisco dressed as Mrs. Doubtfire and no on was the wiser.
Pierce Brosnan, Mara Wilson, Lisa Jakub and Matthew Lawrence spoke with "TODAY" show correspondent Gadi Schwartz in an interview on Wednesday about working with Williams, his impact on their lives and the legacy of the film. Williams committed suicide back in August 2014 amid complications with Lewy Body Dementia.
"Robin was like a guiding source." Lawrence said. "He would just all of a sudden, out of the blue look over and be like, 'Don't do drugs. They really messed up my brain, I'm serious. Do not do them.' That stuck with me."
Wilson, who was only five years old at the time of filming, explained how "great" Williams was with children. "He was very kind, very giving, very funny," she said, adding "There were innumerable times that he made us laugh."
Shwartz asked the cast how they would "describe" Williams. Beginning to tear up, Brosnan replied, "Deeply human, kind, generous, loving."
"A constant performer," Wilson added. "Naturally just so gifted at putting on a show and entertaining everybody around him."
"And at the same time, I feel like deeply authentic," Jakub, who played Lydia in the iconic movie, added. "One of the most powerful things for me about working with him is that he was very open and honest with me talking about his issues with addiction and depression. That was so powerful to me at 14. I have struggles with anxiety my whole life."
See the highlights from the round table below.
Williams Once Went Undercover as Mrs. Doubtfire IRL
Lawrence, 38, revealed that not only did Williams help him get his role during the screen test, but took Lawrence out for a walk in San Francisco dressed as Mrs. Doubtfire.
"Nobody knew," he recalled. "They thought [he was] my nanny. And he played it off and sat down with these other two British ladies. They didn't even know, it was incredible!"
The "Brotherly Love" star said it was just one of the experiences that will "stick with him forever." Lawrence added that he was grateful for Williams also opening up about the dark sides of his personality.
"He had this..almost kind of deep sorrow to him," Lawrence said. "He also shared that with me and it was such a gift to feel...he completely opened up to me with that, just explained it to me."
"For an 11-year-old to get that kind of experience," he added. "I just don't have any other experiences like that."
Everyone's Favorite Scene to Film
Shwartz had the cast go around and name their most memorable scene to film in the 1993 comedy.
Lawrence said that his favorite moment was when his character Chris sees Mrs. Doubtfire peeing standing up and is confused.
Brosnan explained that he enjoyed the "run by fruiting" scene, while Jakub pointed out that the big reveal -- when the kids learn that their Dad, Daniel (Williams), is actually Mrs. Doubtfire -- during the iconic restaurant scene, was by far her favorite of the film.
"It goes from being tense and hysterical to really tender and sweet, which I think it really encapsulates the movie," Jakub added.
The group then dived into discussing the dinner scene. Wilson explained that when she said the simple, yet famous line, "Dad?" she was actually looking at a Polaroid of Williams.
"Just seeing his face got me through that scene," Wilson said. "I didn't realize how devastating it would be to see a young child, as a child of that age, and have that expression. From the outside, it's just like, 'Oh yeah, that's incredibly sad. That's incredibly moving."
Williams Called Jakub's Canadian High School
Schwartz pointed out that Williams once helped Jakub in school. The writer laughed and recalled being a high school student while filming the '90s comedy. Jakub, who is a native Canadian, explained that the country requires a tutor to be present on the set for child actors.
"I was sending my work back to my high school, but it wasn't really working out with my high school," Jakub said. "They were a little frustrated that I was away for so long so they sent a letter, when they sent my school work back, saying like 'Hey, you know when you're done, don't come back. We're kicking you out. It's just a little disruptive.'"
Jakub said that as a 9th grader, the letter was a "traumatic" experience. After seeing how upset she was, Williams stepped in and asked for her principal's information.
Williams sent a letter to Jakub's high school asking them to "reconsider" her expulsion. Although the school didn't change their mind, it was the gesture and lesson to "stand up for what's right" that stayed with Jakub.
"It was just so kind," she said. "He did not need to do that for me."
The Film's Underlying Message and Overall Legacy
Not only did the film immensely impact the actors' careers, but the cast explained how the movie's "empowering" message helped children deal with divorce.
"It kept me employed, I managed to pay the mortgage and look after my children," Brosnan joked. "But it's really ingrained in my heart because the nature of the story, which is very empowering for young men and women or families that are divorced. I think it's a very healing film in many ways."
Schwartz, who said he grew up with divorced parents, thanked the cast for creating a film that helped him cope with his parents' separation and let him know that "everyone would be okay." Jakub and Wilson admitted that people still come up to them and give similar words of gratitude.
"I hear that a lot," Jakub said and Wilson added, "I do too. It's really incredible to know that you had that impact, that you're able to help people...We were children and we got to make people get better about themselves, what more could you ask for, really?"
"Before 'Mrs. Doubtfire,' I think not a lot of movies dealt in a realistic way about divorce," Jakub added. "I think it really showed that there are very different versions of a happy ending and that families might look different, people might live differently than you, but then there's love when there's acceptance, all of those things, it's going to be okay."
"I think that continues to be a powerful message for people," she continued. "That this might not be exactly how it was gonna be, but that doesn't mean that it's wrong or bad or that you're not going to be okay and I think that's something that we all need to be reminded of."
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