The answer to such a question is simple -- the age of these children makes them vulnerable since they are not fully developed cognitively. According to Calvert (2008), “One key area in research on the effect of advertising on children has been analysis of age-based changes in children’s ability to understand commercial messages, particularly their intent” (p. 214). In the article Calvert also mentions that “before children reach the age of eigh, they believe that the purpose of commercials is to help them in their purchasing decisions” (p. 214); they are unaware that commericials are designed to persuade them to buy specific products. Calvert notes that such shifts that take place in children’s understanding of commercial intent can be best explained using theories of cognitive development.