Child actors are expected to perform much the same way adult actors do. They play characters in movies and TV shows, which means they must know their lines, understand their character and show up on time ready to work. Like adult actors, they must often undergo a lengthy auditioning process before they land a part, or demonstrate qualities (usually cuteness) which the filmmakers require for their project.
Unlike adult actors, however, child actors are governed by labor laws (in the United States, at least) which strictly govern their working conditions. Child actors are forbidden from performing nude or semi-nude, they cannot engage in sexual activity, and their safety cannot be compromised in any way (in other words, no stunts). They may only work a few hours each day--the exact amount depends on the child's age--and compulsory education laws mean that they must still be enrolled in school while they are working. (Successful child actors often have a private tutor who instructs them while on the set.) Because many movies and TV shows work overtime, they will seek out sets of twins to serve as child actors: both children can play the same character, and one can rest while the other is working (thus keeping the production on schedule). Mary-Kate and Ashley Olsen are the most prominent example of twins being used in this fashion.
The notion of a self-destructive child actor has become cliche, and its basis in fact can be complicated. Some child actors come from an unstable home life, force to deal with dysfunction and parental insecurities that may have led them to acting in the first place. So-called "pageant mom" syndrome occurs when a parent pressures a child into performing in order to make up for perceived failures or limitations in the parent's own life. Other parents may become resentful of children who enjoy more financial success than they do, or encourage them to work harder in order to keep the money rolling in. The demands of a shooting schedule can make normal routines impossible, and--as with adult actors--work can vanish as quickly as it appears, leading to stress and emotional turmoil which few children are prepared to deal with. Add that to a permissive atmosphere which encourages drug use, experimentation, and "acting out," and many successful child actors end up in deep (and very public) trouble. Lindsey Lohan is the most prominent example of this trend, but the list also includes actors Corey Feldman, Edward Furlong, Tatum O'Neal and Macaulay Culkin.
The term "child actor" can also apply to an adult best known for his work as a child. The stresses there can be difficult as well, as adults struggle to recapture a glory which came far too soon and faded far too quickly. The sense of peaking extremely early in life leads to a feeling of slow decline, which can haunt a child actor in later years. Many burn out and turn to self-destructive habits, but many others simply switch gears: returning to school or picking up new skills that allow them to find new careers. One of the most prominent examples is Carrie Henn, who played Newt in James Cameron's "Aliens." She left acting after that one film and today works as an elementary school teacher in Atwater, California. Another former child actor who stuck closer to the business is Peter Bilingsley, best known as Ralphie in "A Christmas Story." He works behind the scenes as a producer these days--though he still makes occasional appearances in front of the camera--and was one of the forces behind the 2008 hit "Iron Man."
Certain laws have been set into place to prevent the financial exploitation of child actors. The Coogan Law in California (named after former child star Jackie Coogan) decrees that a certain portion of their earnings be set into a locked trust until they reach adulthood. Parents are unable to access those funds without their child's permission, although--as with all familial relations--that doesn't prevent emotional complexities from interfering with the process of de facto ownership.
Despite the horrific stories associated with child actors, there is little evidence to suggest that the show business environment is an active contributor. Though overly permissive surroundings may cause problems, the same holds true for non-acting children as well. Responsible parenting, coupled with a common-sense approach to opportunities can help a child actor lead a healthy and emotionally stable life, just like any other child. It's worth noting that for every child actor in tragic circumstance, there is another who not only succeeded, but went on to a fruitful career as an adult actor as well. Stars like Jodie Foster, Kurt Russell, Natalie Portman and Elijah Wood all started out as child actors only to make the transition into adulthood and continue to work prominently in their chosen profession today.