Hello. I Am Concerned About A Friends Daughter Who Is

Hello.
I am concerned about a friends daughter who is addicted to pain medication. She recently had 5 bypasses and a leaky valve repaired. But she has been taking different pain pills. This past friday, her doctor prescribed her 30 percocets. The daughter claims that someone stole all of them but 2 pills. I personally don't believe the story because this seems to be something that "happens" every time she is given any type of pain medication. I do know her doctors name.
Her parents know people that will sell her their pain medications to give her. I am wanting to know what should I do. Shes going to kill herself from an overdose someday and shes got 2 children.
I appreciate any advice. I just want to help.