sibling rivalry
intense competition among siblings for recognition and the attention of their parents. Sibling rivalry normally begins when a baby is introduced to a family and the older sibling fears the baby will replace him or her. The older child may become extremely jealous and display aggressive behaviour toward the baby or such regressive acts as bed-wetting or baby talk. This regressive behaviour is considered the older child's way to try and reestablish himself in a dependent role with his parents. As the children grow, sibling rivalry can lead to extremely competitive or aggressive behaviour, which may become generalized to other life experiences (e.g., career). Sibling rivalry is by no means universal or inevitable, but seems to depend in part upon how parents balance the sometimes competing needs of offspring.
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