The left-behind children (LBC), separated from their mother/father or parents for a long period of time, have long been discussed as a subject of concern in China. Existing research has concluded that rural children who did not migrate with parents are subject to emotional risks. In the present study, the purpose is to study the impact of parental migration on early emotional understanding. Purposeful sampling was used to recruit 180 children aged five to six years in rural areas of Guangdong province, including LBC and non-left-behind children (NLBC). Their level of emotional understanding (EU) was assessed by the emotional comprehension test (TEC) adapted to the Chinese context. The results showed that, on the three levels (External, Internal, Reflective) of emotional understanding, LBC aged five- to six- years old scored significantly lower than NLBC as counterparts. On the whole, the emotional comprehension ability of preschool LBC was significantly lower than that of NLBC. However, there were no significant differences within LBC nurtured by single parents, grandparents, and other relatives. This study confirmed that parental migration in early childhood considerably impacted rural LBC’s emotional understanding and affectional adjustment, which provided a significant basis for increasing parental care and early childhood companionship in rural areas.

Background Callous-unemotional traits and emotional lability/negativity of young children have been regarded as the markers of externalizing problem behaviors. Based on the sensitivity to threat and affiliative reward model and the general aggression model, emotional lability/negativity may act as a mediator in the relationship between callous-unemotional traits and externalizing problem behaviors. Additionally, a positive teacher-child relationship could act as a buffer given the parental absence in left-behind children. However, these links remain unexplored in left-behind preschool children. Therefore, this study explored the link between callous-unemotional traits of left-behind preschool children and externalizing problem behaviors, as well as the mediating role of emotional lability/negativity and the moderating role of a positive teacher-child relationship. Method Data were collected on 525 left-behind children aged 3 to 6 years from rural kindergartens in China. Preschool teachers reported all data through an online survey platform. Moderated mediation analysis was performed to examine whether the mediated relation between callous-unemotional traits and externalizing problem behaviors was moderated by a positive teacher-child relationship. Results The results showed callous-unemotional traits significantly predicted externalizing problem behaviors and lability/negativity acted as a mediator, while a positive teacher-child relationship acted as a protective factor in moderating the relationship between callous-unemotional traits and emotional lability/negativity. This study identified a moderated mediation effect among the four variables in left-behind preschool children in China. Conclusion The findings provide support for the advancement of theoretical foundations, and provide an avenue for further exploration to support the mental health and overall development of left-behind children during early childhood.