Sibling rivalry: When the family circle becomes a boxing ring

DR. ANDERSON is clinical professor of pediatrics, University of California, San Francisco. She has nothing to disclose in regard to affiliation with, or financial interests in, any organization that may have an interest in any part of this article.

The words "sibling" and "rivalry" fit together like "boxing" and "glove." The first story of siblings in the Bible, for example, describes Cain murdering his brother Abel because Abel's sacrifice was more acceptable to God. Sibling rivalry is understood to mean the jealousy that develops between brothers and sisters as they compete for parental time, attention, love, and approval. Brotherly love does not develop naturally; in fact, extremely difficult sibling conflicts have been linked to long-term antisocial behaviors during adolescence. Fortunately, following some basic guidelines can help parents lessen the natural jealousy and friction between their children. You are in a unique position to provide parents with anticipatory guidance when a new baby is expected, teaching parenting principles that will help everyone adjust to a larger family.

Round 1: The child's perspective

These changes often occur as the firstborn child is entering the "terrible twos," attempting to define her own identity, determine the rules of her family and society, and decide how she can explore her environment. The toddler may not have the cognitive ability to express her emotional needs, and therefore demonstrates antagonistic behaviors toward the intruder who has upset her world.

What is jealousy?

Jealousy comes from the Latin meaning "full of zeal" and is used today to mean "apprehensive of rivalry" or "envious."¹ Jealousy is a complex emotion-usually comprising anger, sadness, and fear-that can occur only within the context of social interactions. A person cannot be jealous unless two other people are involved in what social scientists refer to as a "social triangle." "What is always true is that jealousy involves a triangle of relations."² In the case of siblings, the three relationships within the social triangle are:

Jealousy can occur only within a valued, close relationship and is precipitated by the perceived or real loss of the relationship-in the case of siblings, the perceived threat to the child's relationship with the parent(s). You can use this definition to reassure parents, reminding them that a child cannot feel jealousy or be concerned about a loss of relationship with his parents unless he has a close relationship with them to begin with. A child who does not feel valued by his parents does not feel threatened when another child enters the family.

Jealousy can provoke many behavioral responses, including withdrawal or fear; acting out or anger; and avoidance of the social situation. Volling and colleagues describe jealousy as "an organized complex of emotions, cognitions, and behaviors following the threat to or loss of a beloved relationship to a rival."² Children may respond to their feelings of jealousy by attempting to interfere with the rival sibling's relationship with the parents, seeking support from others (friends, relatives), speaking poorly of the sibling, avoiding the social situation, or developing a different source of happiness (playing with a different toy, spending more time with friends).