Actors you may not know are dead

When we watch celebrities at the movies or on TV, we develop special bonds with them. So when they're gone too soon, it can be devastating—especially when we don't realize we've lost them. You may not know some of these actors by name, but you certainly know their faces. Some of your favorite movies or shows feature actors that have been taken from the world well before their time.

Lee Thompson Young's star vehicle, The Famous Jett Jackson, was a very popular show on The Disney Channel for some time, which also featured Rachel McAdams, who at the time was an up-and-coming star. Friday Night Lights, Akeelah and the Bee, and The Hills Have Eyes II are some of the few films on Young's impressive resume. He had been diagnosed with Bipolar Disorder while working as a series regular on Rizzoli and Isles. Then, on August 19, 2013, his life came to a tragic end after committing suicide with a self-inflicted gunshot wound.

After rising to fame in 1995's cult classic Clueless with the famous line "You're a virgin who can't drive," Brittany Murphy offered strong performances in Girl Interrupted, Drop Dead Gorgeous, 8 Mile, and Sin City. Murphy was the breadwinner of the family, as she cared for her mother, a breast cancer survivor, and her husband, Simon Monjack, who suffered from frequent seizures and heart troubles. While the circumstances of her death are suspicious, Murphy was declared dead on December 20, 2009, due to pneumonia, anemia, and multiple drug intoxication. It is unclear whether "toxic mold" also played a part in her untimely death at age 32, as her husband was found dead in the same house five months later.

Best known for playing Carol Anne from the movie Poltergeist, Heather O'Rourke was the sweet young girl that terrified audiences after being sucked into the television set. She was also one of a very small number of original cast members that remained with the movie series until Poltergeist III. If you've seen the final movie, you will notice Heather's cheeks are very puffy—a reaction to the medication she was taking for Crohn's disease, with which she was misdiagnosed. Tragedy struck when Heather suffered from cardiac arrest while undergoing a surgery for a bowel obstruction at the tender age of 12.

Renfro skyrocketed to fame at age 11 by starring in Joel Schumacher's adaptation of The Client by John Grisham. High profile roles followed, and he made appearances in Sleepers opposite Brad Pitt, Ghost World alongside Scarlett Johansson, and The Informers starring Kim Basinger. Renfro fulfilled the sad destiny of many child actors, plunging into a life of illegal drug use and trouble with the law. After pleading no contest to attempted possession of heroin—he'd tried to buy drugs from an undercover L.A. police officer—Renfro spent ten days in jail. On January 15, 2008, at 25 years old, Brad Renfro was found dead of an accidental heroin and morphine overdose in his apartment in Los Angeles.