The focus of this study involved the study of siblings over the age of 30. Specifically of interest was the relationship between verbal aggressiveness, credibility, satisfaction, and trust. Recruited participants were informed in a cover letter that this study involved communication in sibling relationships and that they needed to have a sibling in order to participate. Participants reported on their use of verbal aggression in their sibling relationships, their perceptions of their siblings' credibility, and how much trust and satisfaction they currently had in their sibling relationships. Results showed a negative relationship between the amount of verbal aggression in the relationship with perceptions of credibility, trust, and satisfaction. Trust and satisfaction were positively related to all three dimensions of credibility (competence, character, and caring). The sibling relationship is a forced relationship that is often later maintained by the participants to create a life-long relationship (Cicirelli, 1995; Fitzpatrick & Badzinski, 1994; Noller & Fitzpatrick, 1993). While attention is often paid to conflict and sibling rivalry, most people report being satisfied in their relationships with their siblings (Floyd & Parks, 1995). Brothers and sisters play various roles for their siblings, including the roles of friend, competitor, manager, and teacher (Buhrmester, 1992). Additionally, people look to their siblings to provide companionship, comfort, affection, and friendship (Goetting, 1986). The more emotional closeness shared between siblings, the greater the contact and commitment the siblings will have during their lifetimes (Lee, Mancini, & Maxwell, 1990). Seemingly, the communication that takes place between siblings would influence the quality of the relationship. This study attempted to learn more about the communication and relational outcomes in the sibling relationship by studying siblings over the age of 30. Specifically of interest were the relationships involving verbal aggressiveness, credibility, satisfaction and trust.