Nora T. is believed to have witnessed the agonizing death of her 5-year-old Yazidi daughter while they were both kept as slaves by a couple affiliated with "Islamic State" in Iraq in 2015.

German national Jennifer W. is on trial in Munich for the war crime of allowing the girl to die of thirst while she was chained up in 45-degree heat as a punishment for wetting the bed. Prosecutors have said that while Jennifer W.'s husband chained the girl, she did nothing to prevent the girl's death.

According to the Yazidi human rights group Yazda, it is the first trial worldwide based on charges involving crimes of IS members against the Yazidi minority.

The 47-year-old Nora T. is a key witness in the trial against 28-year-old Jennifer W., who is believed to have been involved with IS from September 2014 to 2016. In court, she wore a black jacket, white blouse, and black-rimmed glasses. She did not look at Nora T. or show any emotion, according to DW correspondent Matthias von Hein.

Read more: Who are the Yazidis?

Nora T. unsure about her daughter

Jennifer W. and her Iraqi husband, Taha A., an IS fighter, allegedly bought the Yazidi girl and her mother as household slaves in 2014. Jennifer W. allegedly served in an "anti-vice squad" for IS that patrolled parks in Fallujah and Mosul and forced women to adhere to IS' strict rules and regulations.

Taha A. was arrested in Greece in May, shortly after Jennifer W.'s trial had started.

Nora T., who was dressed in black and wore a headscarf, looked distraught when she entered the courtroom, according to von Hein.

The 47-year-old cannot read and only attended school for four years. She spoke Kurmanji, a Kurdish dialect, which the interpreter seemed to be struggling with at times. Nora T. appeared to be unsure when asked questions about her daughter, at one point saying she could not remember when she was born.

Read more: Nadia Murad: One woman's fight against Islamic State

When asked about her daughter's name, she said the daughter was called Rania, which was the name given to the girl by IS. On further questioning, she said the name was Rullah. When the judge asked if she had said "Reda," she said yes.

Judge Reinhold Baier took his time during questioning. He asked her about the traumatic events that had changed her life and the IS genocide against the Yazidi people in Iraq. Nora T. was abducted in 2014 while trying to flee the advancing IS fighters, together with her three children. They were later separated in the Iraqi city of Mosul.

Nora T. confirmed that she has two sons and a daughter, but added that she was not sure about her sons' whereabouts.

Read more: Germany turning away more Yazidi refugees

Editor's note: Deutsche Welle follows the German press code, which stresses the importance of protecting the privacy of suspected criminals or victims and obliges us to refrain from revealing full names in such cases.