Robin Williams reportedly told his teen Mrs Doubtfire co-star Matthew Lawrence to avoid doing drugs when they worked together in 1993.

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Lawrence recalled the interaction in a recent interview with People, saying that the late actor spoke to him about his struggles with substance abuse.

“He was the first adult who really let me in on his condition. Like, full-on let me in,” Lawrence said. “I mean, as bright as he was on camera — I would go visit him in his trailer to talk to him — it was painful for him. It’s really painful for him. He didn’t hide it. He talked to me about it.”

The actor went on to say that Williams had said to him: “Don’t ever do drugs. Especially cocaine.”

“He was very serious,” Lawrence added. “He was like, ‘You know when you come to my trailer and you see me like that?’ He’s like, ‘That’s the reason why. And now I’m fighting for the rest of my life because I spent 10 years doing something very stupid every day. Do not do it.’ I stayed away from it because of him.”

Lawrence played Chris Hillard in the comedy, opposite Williams in the titular role. He won the Golden Globe for his performance, and the film took home the Oscar for makeup and hairstyling.

Last year, Williams’ children Zak and Zelda paid tribute to their father on the seventh anniversary of his death.

“Dad, seven years ago today you passed on,” Zak wrote. “The joy and inspiration you brought to the world carries on in your legacy and in your family, friends, and fans you so loved.

“You lived to bring laughter and to help others. I will be celebrating your memory today. Love you forever.”