Favoritism, Jealousy, and Conflict in Sisters, Brothers, and Siblings Aggression

Through this chapter, a broad view is provided on how motherly and fatherly favoritism, jealousy, conflict, and aggression manifest in sibling dyads. Key research on understanding these variables is cited, along with literature generated within the context of Mexican culture that gives meaning to these variables and discusses their particularities. Additionally, for each of these aspects, measures designed and validated specifically for emerging adults from this cultural group are presented. The aim is to gain a deeper and broader understanding of the emic manifestation of these aspects. With valid and reliable psychological tests, this chapter aimed to investigate the prediction of aggression based on other variables in sisters, brothers, and siblings. Interestingly, it was found that possession (a jealousy factor) predicts sibling aggression in all three dyads, while each dyad incorporates other predictors examined from the perspective of Mexican culture. The results are extensively discussed regarding how emerging adults construct their sibling relationship in unique ways based on these aspects considered harmful to them.