Mischa Barton lights up

Last month, actress Mischa Barton's younger sister, Hania was admitted to a rehabilitation center to get over her addiction to prescription drugs. And now, to the dismay of her parents, Mischa is caught up in her own drug controversy.

Pictures of Mischa smoking a joint in her car recently surfaced on the Internet. A source for Australian tabloid NW said, "This couldn't come at a worse time. Mischa's family is furious with her tacky timing. It looks like they are the worst parents in the world and that both their daughters are out of control and strung out on drugs."

Mischa was likely using marijuana to numb her recent pain. Last month was difficult for the actress as, in addition to her sister's admission to rehab, she split with her longtime boyfriend, musician Cisco Adler. Understandable as her drug use is, Mischa's parents were disappointed in her decision to smoke in her car. An insider said, "Mischa's parents can't believe she'd be dumb enough to smoke and drive. Look at what happened to Nicole Richie. She's facing time in jail if convicted for her recent 'drug-driving.'"