Because sibling disagreements are inevitable, such experiences are instrumental in developing effective communication skills. Siblings need to learn how to negotiate and compromise on their own, and parents must resist the urge to intervene. Age differences often lead to arguments over privacy, and older siblings may accuse their younger sibling of invading their personal space. Sibling trust is directly related to sibling communication over personal boundaries and personal items; the older sibling is instrumental in this process.

Siblings imitate each other, and younger siblings especially imitate their older ones. In fact, older siblings have a profound influence on the development of language and overall cognitive growth in the younger sibling. Communication may occur through parental interaction with the older sibling. For example, when an older sister is punished for breaking curfew, the younger sibling implicitly receives information about age-appropriate behaviors.

Communication always occurs within a context. The shared experiences of siblings provide a seemingly endless array of environments to encounter communication styles. For example, when an older sibling has a history of deviant behavior, younger siblings may witness parent-child arguments. Or if a family visits an older sibling at college, the younger child may experience positive interactions. Over time, the varied experiences accumulate, creating shared communication patterns -- unique to the siblings.

Siblings and stepsiblings share at least one common element: parents. When siblings are engaged in positive conversation about their parents or conspiring to circumvent a rule, they are actively communicating. Older siblings often impart -- even if implicitly -- strategies to negotiate parental boundaries. The younger sibling is constantly learning problem-solving skills and appropriate behavior by witnessing punishment and praise bestowed on the older brother or sister.