Rossa was the son of Vice admiral Connaught Rossa and the brother of Connor Rossa. He was killed in action at the Krasner outpost.
William T. Riker mentioned hearing of "another Rossa"'s death after learning in 2367 that Jono was really "Jeremiah Rossa". Jean-Luc Picard observed that the family was no stranger to tragedy, as both he, Connor, and Connor's wife Moira Rossa had all met with tragic ends. (TNG: "Suddenly Human")
This man was only mentioned in dialogue.