The Western Cape High Court is expected to hear Marli van Breda's future care arrangements and whether the current curator's appointment should be extended on Monday.
Van Breda's brother, Henri, was sentenced to three life sentences for the murder of his mother, father and brother, and another 15 years for the attempted murder of his sister.
The sentences will run concurrently.
The court will hear the proceedings on Monday after it was postponed last month to allow the curator, Louise Buikman, to allow her to file her report.
Buikman had been appointed by the court three years ago after Marli's parents Martin and Teresa, as well as her oldest brother Rudi, were killed in an axe attack at their lavish De Zalze Golf Estate home in January 2015.
Marli survived the attack, but sustained serious brain injuries and suffered from retrograde amnesia.
In October 2016, Buikman's curatorship was extended despite Marli having turned 18.
She was authorised to continue to act on behalf of Marli and to assist her in legal proceedings as well as all "major decisions".
In September last year, prosecutor Susan Galloway said Marli had indicated to the State that she would not be available to her brother's defence.
Shortly after his sentencing last week, Henri van Breda indicated he would appeal his conviction and sentencing. He has since the beginning of the trial maintained his innocence.
The appeal has been set down for June 27.
During sentencing proceedings, Judge Siraj Desai said: "These attacks display a high level of innate cruelty and an almost unprecedented disregard for the welfare of one's own family, one's parents and siblings. Each murderous attack upon a family member constitutes a very serious crime, warranting the severest penalty possible.
"Viewing all these acts cumulatively, it must rank extremely high on the ladder of serious crime."