A crane operator, who was considered a "father" by an alleged rape victim, said the accused's wife had helped to remove the victim's jeans during the alleged rape.

Giving testimony in the High Court on Thursday on the fourth day of an ongoing trial, the crane operator, who is the boyfriend of the victim's mother, said this was what the 21-year-old had told him after the incidents that took place in March 2010.

The girl, who is intellectually disabled and 18 at the time of the alleged incident, had also told him that instead of stopping her husband, the accused's wife "encouraged" the rape to happen.

"When she (the victim) said this to me, she was crying and in fear," the crane operator said. He added that he had known the victim since birth and would send her to primary school when she was young. He cannot be named as this could lead to the victim's identification.

The victim was allegedly raped by her 39-year-old half-brother over two nights in March 2010 when she was staying in his one-room flat. It emerged in court on Monday that she had sex in a hotel with a stranger who approached her just one or two days after the alleged rape. And on Tuesday, the accused's wife had broken down while giving her testimony. She had insisted that nothing happened on the first night and that on the second night, it was the victim who had wanted to have sex with her husband.