But these programs are aimed at teenagers. The teens' parents were also interviewed. Society gives one gender role to girls, and another to boys. Boys who do are often bullied, teased and beaten. Children who do not follow them can be made to feel unhappy with themselves. They are expected to be passive or quietly accept what others tell them to do or do to them. The new study suggests that by the teen years it is already too late. It can make some boys fall into using drugs. Stereotypes that emphasize physical strength can make boys more likely to get into fights. The study found that young children learn to think of girls as weak and helpless, while boys are seen as "strong and independent." Stereotypes that emphasize physical strength can make boys more likely to get into fights. In all 15 countries, gender stereotypes for girls emphasize that females are passive. These children are at risk of killing themselves or being killed, the study warns. An example is how girls are expected to play with dolls. They are strongly established in a child's mind by age 10 or 11, study leader Kristin Mmari says.