Robin Williams’ co-star in Mrs. Doubtfire will never forget the lessons the late actor taught him. Speaking toEntertainment Weekly in an interview published Thursday, Matthew Lawrence, who played Williams’ son in the ’90s classic, described working with the Oscar winner as the “biggest learning curve.” “I didn’t quite realize it at the time, but that moment there on set of Mrs. Doubtfire, that those six to eight months were the biggest learning curve anyone can get when it comes to making movies and being an entertainer,” Lawrence said, adding that Williams taught him the “type of compassion you need to have for people” and to not “judge until you walk in someone else’s shoes.” Williams, who was often vocal about his struggles with substance abuse, also warned Lawrence to not “put that stuff in your body.” “He really opened up with me, and I’ll never forget it,” Lawrence, now 45, said. “There were times he would just grab me and he’d be like, ‘Don’t put that stuff in your body. If I could go back and tell myself, this is why I’m telling you, don’t put that stuff in your body.’”