Siblings are often a source of emotional support for one another. In healthy relationships, siblings help one another overcome difficulties by listening to grievances and offering advice. This support is often vital for siblings experiencing life's adversities, including parental discord, divorce and foster care placement. The relationship helps siblings realize that they are not alone and allows them to share private and difficult information with a trustworthy confidant.

Kids Health notes that it is common for siblings to compete and fight with one another for various reasons, such as vying for attention or because of their individual temperaments. This competitiveness, or sibling rivalry, is often a source of frustration for both siblings and parents, and as such, can be considered a negative aspect of sibling relationships - especially if the rivalry turns violent or abusive. A 2012 University of Michigan Health System report found that situations where a child is victimized by a sibling are common.

Siblings teach each other essential social skills, such as how to manage conflicts and negotiate with others, notes Child Welfare Information Gateway. Phil Ciciora-Illinois, contributor to the research portal Futurity, notes that siblings model appropriate social behavior for one another, such as how to act at school and how to appear "cool" among peers. Siblings can use these skills in their social circles and create healthy relationships with people outside of their immediate family.

Perceived favoritism is a common, negative aspect of sibling relationships. Carl Pickhardt, Ph.D., psychologist and contributor to Psychology Today, states that favoritism leaves the less favored child feeling inadequate, while the favored sibling can develop a sense of entitlement. Pickhardt recommends that parents refrain from comparing siblings to one another and embrace and praise the differences in their children. Kids Health recommends that parents avoid creating the perception that one child's needs are favored over that of another by staying out of sibling conflicts.