1. Introduction {#sec1-ijerph-17-03700} =============== The recent evolution of social media has made us more connected than ever before. With more than a billion active users per month \[[@B1-ijerph-17-03700]\], users are constantly exposed to large amounts of persuasive messages on various platforms, including WhatsApp, Instagram, YouTube, Facebook, and TikTok. The wide reach of social media has also been linked to increases in attention deficit and hyperactivity disorder symptoms, particularly with younger age \[[@B2-ijerph-17-03700],[@B3-ijerph-17-03700]\]. Given that our attention can be easily distracted, especially by content related to social comparison and appearance evaluation \[[@B4-ijerph-17-03700]\], children are the most vulnerable group to such social media exposure and become targets for their persuasive content and advertisement \[[@B5-ijerph-17-03700],[@B6-ijerph-17-03700],[@B7-ijerph-17-03700]\]. Social media companies heavily rely on users' self-presentational needs to increase the likelihood that they can access to potential consumers. By using persuasive content and brand marketing, social media companies seek to fulfill their users' self-presentational needs, which is the act of presenting oneself in a way that is likely to be viewed favorably by others \[[@B8-ijerph-17-03700],[@B9-ijerph-17-03700]\]. One example of such persuasive content is the ubiquitous "Like", the use of which has been shown to be the most powerful tool for gaining friends and achieving popularity online \[[@B10-ijerph-17-03700]\]. One study found that "Like" is seen by children as an indicator of likability, popularity, and popularity increase \[[@B5-ijerph-17-03700]\]. Social media companies utilize a number of strategies to persuade their users. For example, they are inclined to use emotionally compelling and persuasive content \[[@B11-ijerph-17-03700],[@B12-ijerph-17-03700]\], to frame messages in terms of social comparison \[[@B13-ijerph-17-03700],[@B14-ijerph-17-03700],[@B15-ijerph-17-03700],[@B16-ijerph-17-03700],[@B17-ijerph-17-03700]\], and to manipulate the content's appearance to be more favorable than it actually is \[[@B18-ijerph-17-03700],[@B19-ijerph-17-03700]\]. Additionally, they typically employ persuasive strategies in order to increase their company value \[[@B8-ijerph-17-03700]\]. As a consequence, the number of likes on a specific post has become an important indicator in various aspects of our daily lives, such as career, interpersonal relations, personal evaluation, and employment opportunities \[[@B6-ijerph-17-03700],[@B20-ijerph-17-03700],[@B21-ijerph-17-03700]\]. Social media companies frequently use their users as research subjects to study and enhance the effectiveness of their persuasive content \[[@B14-ijerph-17-03700]\]. For example, they have been found to strategically place their persuasive messages \[[@B4-ijerph-17-03700]\], to alter words and metaphors in their advertisements \[[@B22-ijerph-17-03700],[@B23-ijerph-17-03700]\], and to display persuasive content which is related to people's everyday life \[[@B16-ijerph-17-03700],[@B24-ijerph-17-03700]\]. While social media companies have an interest in studying users' attention to and perceptions of persuasive messages, previous research has focused on adult users, who are considered "end users" of social media \[[@B25-ijerph-17-03700]\]. It is now important to extend research on persuasive content to younger age groups, in particular, to children, who are in the period when the self-concept formation becomes apparent \[[@B26-ijerph-17-03700]\]. This study fills a significant gap in this field of research by examining persuasive messages targeting children. Specifically, the current research aimed to answer two research questions: (1) what are the characteristics of children's persuasive messages on social media, and (2) what are the persuasive features that contribute to these persuasive messages. 1.1. Characteristics of Children's Persuasive Messages {#sec1dot1-ijerph-17-03700} ------------------------------------------------------ Previous research suggests that children are attracted to peer-to-peer communication, but not necessarily by the persuasive content that accompanies this communication. For example, a survey conducted by Buhrmester, Kwang, and Gosling \[[@B27-ijerph-17-03700]\] found that more than one in five children between the ages of 7 and 10 engaged with the internet for reasons related to social interaction, compared to 20% of children in Buhrmester's \[[@B28-ijerph-17-03700]\] original study of the 1980s, indicating that the opportunity to communicate with others through the internet has broadened the context and nature of peer interactions. Children would consider whether a peer friend has posted or forwarded a message before responding to it \[[@B29-ijerph-17-03700]\]. When peers engage in conversation or communicate in the form of text message, children often try to determine what other people will think about them based on their contribution to the conversation \[[@B30-ijerph-17-03700],[@B31-ijerph-17-03700]\]. Such a context may be especially compelling to children because they are in a phase of establishing a unique self-image \[[@B32-ijerph-17-03700],[@B33-ijerph-17-03700],[@B34-ijerph-17-03700]\]. However, the types of persuasive messages on social media can impact the nature of the messages children will receive. Research has shown that children are more willing to engage with persuasive content that is perceived as relevant to them, including their self-identity, daily experience, and social experiences \[[@B35-ijerph-17-03700],[@B36-ijerph-17-03700]\]. Children who perceive advertising messages to be relevant to their lives will also give more attention to those messages \[[@B37-ijerph-17-03700]\]. In fact, in terms of their self-concepts and attitudes toward peers, children have been found to be more susceptible to messages that are personally relevant \[[@B38-ijerph-17-03700],[@B39-ijerph-17-03700]\]. While much research has examined the characteristics of persuasive messages, little research has focused on how persuasive content can be tailored to increase the appeal of a particular persuasive message. Previous research has examined how adults respond to persuasive messages on social media, which can be classified as brand image maintenance (BIM), brand image enhancement (BIE), product information (PI), and brand image (BI). In the BIM condition, the advertisements focus on brand information with the goal of ensuring that the product is associated with the brand and is an expected part of the experience with the product. In the BIE condition, the advertisement emphasizes the product feature, but also provides information on the brand and its image. The PI condition refers to messages that provide information about a particular product, but does not focus on the brand \[[@B9-ijerph-17-03700]\]. The final condition, BI, concerns messages that highlight the brand and its image, often through a celebrity endorsement, for example. Research on children's use of social media has shown that adolescents often engage in brand awareness and brand image maintenance tasks as part of daily information seeking and sharing \[[@B40-ijerph-17-03700]\]. However, this is not the case for younger children, for whom brand awareness is related to social influence \[[@B41-ijerph-17-03700]\]. In other words, younger children were more likely to pay attention to persuasive messages that focused on a single brand than to messages providing other forms of information \[[@B42-ijerph-17-03700],[@B43-ijerph-17-03700]\]. This is especially so when the message is personalized to the child in terms of their gender or preference for certain products, such as sports clothing \[[@B44-ijerph-17-03700],[@B45-ijerph-17-03700]\]. Although social media is becoming a part of children's everyday life, the characteristics of children's persuasive messages are not well understood. In order to understand children's perceptions of the persuasive messages in this field of study, we need to establish a conceptual model of children's perceptions of the persuasive messages they receive on social media. 1.2. Mechanisms through which Persuasive Messages are Delivered {#sec1dot2-ijerph-17-03700} --------------------------------------------------------------- While there has been a large amount of research on the characteristics of persuasive messages, very little research has been done on children's persuasive messages on social media \[[@B46-ijerph-17-03700]\]. Considering that previous research has established that children respond to persuasive messages in an attention-based fashion, we suggest that an understanding of children's attention processes and what attracts their attention can be applied to understanding the persuasive messages they engage with. Research on attention mechanisms has suggested that attention is driven by three factors: (1) salience, which is defined as a property of the stimulus, (2) bottom-up processing, which refers to the automaticity of the processing of information, and (3) top-down processing, which refers to the accessibility of information as a function of goal intentions \[[@B47-ijerph-17-03700],[@B48-ijerph-17-