behaviours of a narcissistic sibling:Self-Centeredness: Narcissistic siblings demand attention and expect things to go their way, disregarding others' needs and feelings.Jealousy and Projection: They mask insecurities by projecting jealousy onto you, belittling your achievements and relationships.Put-Downs to Boost Themselves: They elevate themselves by diminishing your accomplishments and making critical remarks.Transactional Interest: Their engagement is often self-serving, only showing intere