On Monday, a 10-year-old boy took the witness stand to testify against Nicki Minaj’s brother in a child rape case.

The boy, who was 8 at the time he saw Jelani Maraj rape his sister, who was 11 at the time, detailed “what happened was I was looking for [her],” referring to his sister.

He said that he saw his sister’s pants “around her ankles” and “his underwear close to his knees.”

“I thought it wasn’t right. It looked weird to me, so I ran upstairs,” he told prosecutors.

The boy said that Maraj came after him later and slapped him in the face “about 10 times.”

“He asked me if I had seen anything. I said, ‘Yes,’ ” the boy said. “He slapped me on the cheek.”

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The boy claimed that Maraj threatened his mother, Jacqueline Robinson, who he was married to at the time, in order to force the boy to be silent.

“Jelani said I wouldn’t see her again if I told on him,” he said. “His face was kind of mad.”

The boy said that he would also sometimes hear his sister’s door close and then hear her bed creaking. Her bedroom was right next to his.

Prosecutors claimed that Maraj had sex with the girl at least four times a week, though defense lawyer David Schwartz tried to cast doubt on the little boy’s testimony by getting him to admit that the lights were off when he allegedly saw Maraj with his sister. The defense has also claimed that the entire rape trial is an extortion scheme by Robinson to get $25 million from Maraj’s sister, Nicki Minaj.

Last week, a doctor confirmed that the now 14-year-old girl’s medical record is consistent with someone having sex with her.

“I can say with a reasonable degree of certainty that [the girl’s] medical exam can prove penetration,” said Dr. Aaron Miller after reviewing photos of the girl.