Rhombur, was unable to conceive children due to the injuries he had suffered due his debilitating wounds received at the attempted assassination of Duke Leto Atreides I years earlier, so Bronso was born from the artifical insemination from the sperm of the dead Tyros Reffa, who was Rhombur's half-brother, with the egg of his mother.
War of Assassins
As House Vernius came to Caladan to attend the upcoming nuptials of Leto and who would have been his first wife, Ilesa Ecaz; Bronso and his parents attended the wedding. Sadly, Hundro Moritani decided to seek his revenge against House Ecaz on that day, and both Ilesa and her father's Swordmaster bodyguard perished. Bronso, nor anyone in his family, were hurt on that day.
During the night in Castle Caladan, Bronso's good friend Paul Atreides and himself were readied to be attacked by disguised House Harkonnen/House Moritani assassins during the middle of the night as they slept. Paul and Bronso awoke as the assassins approached Paul's bedroom, and the duo surprised and attacked the assassins first, and disbaled the attempted murderers before they struck. The assassins committed suicide before they could be questioned. Bronso returned home to Ix with his parents a few short days later, as Paul and Duncan Idaho fled to Caladan's sparsely populated Eastern Continent.
Loss of Tessia Vernius
When Bronso was 13-years of age, he and his parents were visited by Lady Jessica Atreides and Paul in Vernii City on Ix. Paul was being left by Jessica to be schooled by House Vernius, as the two House Majors engaged in a long noble tradition of having their heirs learn on each others home-worlds. Just after the Atreides arrived, in secret, Bronso's mother was put into a mental coma by the Bene Gesserit psychic eneregy guilt-caster Stokia and her entourage', for Tessia's disobedience to the Sisterhood.
Neither the long time Suk Doctor of House Vernius, Dr Wellington Yueh, nor his assistants, could fathom the deep coma that Tessia found herself in. Bronso, because of the hostility that the Ixian technocrats felt for his family, assumed that it was them, led by their leader, Bolig Avati, who had somehow poisoned his mother. The Bene Gesserit women offered to take Tessia to Wallach IX, and said that she suffered from extreme mental stress, and that only they could help her.
Joining the Jongleur Performing Group
Rhombur Vernius, unaware of who or what had caused his wife's condition, then told Bronso of his true male parentage by way of Tyros Reffa. Over-reacting, Bronso ran away from Vernii City, and Paul, under an oath to Duke Leto "to protect Bronso", accompanied him. They first stowed away aboard a Guild Heighliner, and were let off on Chusuk.
Paul and Bronso were quickly picked up by a Jongleur theatrical production company, and began to learn the basic way that the Jongleurs put people under mass hypnosis as they performed. As the entire troupe stood still, the Jongleur Face Dancer leader and fellow performers began to use their techniques. Bronso saw a majestic play, filled with adventure; but Paul saw a group of people simply waving their arms. The Jongleur leader was amazed at Paul's great ability to resist hypnosis.
Death of Rhombur
Soon afterwards, Bronso and Paul traveled with the performers to Balut, where the duo was discovered by their parents shortly thereafter. A day later, Paul was able to figure out an assasination attempt that was to occur in that planet's Theater of Shards, a glass performance hall that contained millions of pieces of mirrored surfaces. Paul saved the life of the planetary Governor, Alra Kio and her fiance', but sadly Rhombur was killed as he sacrificed his life to save the life of Bronso. Just before Rhombur died, he whispered his last words to his son, "Is Paul safe?" This caused Bronso to be bitter, and to cast House Atreides out of his life.
His death-cell interview suggests that he was to be executed, however excerpts from Analysis of History places him alive after Muad'dib goes into the desert.