The Rossario family were one of the crime families on the Commission until 1998. They were close allies of the Clericuzio family and Don Rossario was a personal friend of Domenico Clericuzio, and this friendship lead to the Clericuzios treating him with warmth and respect. The family was known to be rivals with the Borgetto family, both in business and due to the Don's personal dislike of their use of Neapolitans.
In 1998, Don Rossario was assassinated whilst at the movie theatre with his grandson, an event which was laid at the feet of the Borgettos, though it was later discovered to be part of a plan by Billy De Angelo to start a mob war and take over as Don Clericuzio. Whether the Rossario family continued to operate after the Don's death is unknown.