Rosa is the mother of Jowy Atreides and wife of Marcel Atreides, a Kyaro nobleman. She is Jowy's only known relative, as she had Jowy from a previous marriage; little, if anything is known about her first husband. Rosa enjoyed a comfortable life as a noble at the Atreides estate in Kyaro and was able to provide Jowy with a decent childhood. However, she was unable to curtail the dislike that Marcel and his son, Marco Atreides, expressed for Jowy.
Marcel disowned Jowy and cast him out of the Atreides household, predicated on the belief that he was a Jowston spy. Rosa was not able to see Jowy before his disownment, because Marcel did not permit him to see her. Marcel also told Jowy that Rosa didn't wish to see him, a statement Jowy knew was a lie.
After Jowy became King of Highland, Rosa left Highland with her husband and step-son and relocated to Harmonia, as Marcel feared retribution from Jowy, whom he had treated poorly during his childhood. It is presumed that Rosa has not seen Jowy since his disownment.