Matthew Lawrence, who costarred with Robin Williams in "Mrs. Doubtfire," says the late actor opened up to him about the dangers of substance abuse.

"And then on top of that, you get a chance to be around Robin Williams and he takes an investment in you, as he does with people. But in particular, he really took an investment w

Actor and comedian Robin Williams left a lasting impression on his young "Mrs. Doubtfire" co-star Matthew Lawrence, who said in