Johannesburg - Henri van Breda’s sister Marli could testify against him in his trial on charges of killing their parents and brother.Marli, 17, is number 113 on the list of 114 state witnesses, Netwerk24 reported on Sunday.Henri, 21, is accused of killing his parents, Martin, 54, Teresa, 55, and his brother Rudi, 22, in their home on the De Zalze golf estate in Stellenbosch in the early hours of Tuesday, January 27, 2015. The killer used an axe.Henri would face three counts of murder, one of attempted murder, and one of obstructing the course of justice. He handed himself to police in June and was granted bail of R100 000 on June 14.Marli sustained serious brain injuries in the attack. She suffered from retrograde amnesia and it was still unclear if she would be able to remember anything about what happened that morning.READ: 8 things you should know about the State's case against Henri van BredaAfter Marli's recovery, she saw her brother again. However, the two would be separated again. It was one of Henri's bail conditions that he could not contact anyone on the list of witnesses until the end of his trial.A pre-trial hearing was scheduled in the Western Cape High Court for September 9. The prosecution and defence would have to determine which allegations were disputed and which not. This would determine which witnesses the State needed to call on to prove its case.Susan Galloway is a seasoned senior advocate and successfully prosecuted Najwa Petersen for the murder of her husband, music legend Taliep Petersen.Henri was being represented by Pieter Botha, who was part of Shrien Dewani's legal team.Also on the list of possible witnesses was Victor Isaacs, a paramedic who treated Henri, and Martin Locke, a former TV sports anchor and neighbour of the Van Bredas.