NEW YORK (CBSNewYork) — A child survivor took the stand in Brooklyn on Tuesday in an emotional day of testimony against the man accused of stabbing her and killing her best friend.

The prosecutor called it a case of childhood innocence violently destroyed. 11-year-old Mikayla Capers, in her blue sweater and white tights, came face to face with Daniel St. Hubert.

He’s the stranger accused of stabbing her nearly four-years-ago, and stabbing her best friend, PJ Avitto, to death.

“We noticed a mysterious man,” Mikayla testified.

It was June of 2014, Mikayla was seven and PJ was six at the time, when the two children were playing outside in their city housing development in East New York when the two went inside to get ices.

Mikayla pointed out St. Hubert in court, saying he was the mysterious man in the lobby who followed them into the elevator.

“He told us to shut up,” she said. “I felt anxious.”

Then, Mikayla said, St. Hubert started “repeatedly stabbing” them. When he stopped, she said St. Hubert ran out and she knew PJ was dead.

“His eyes were open,” Mikayla said. “There was a bunch of blood on the floor.”

Defense attorney Howard Greenberg called Mikayla “unworthy of belief.” On cross-examination, he tried to poke holes in the child’s story, getting her to admit she tells white lies sometimes.

He also questioned her about seeing St. Hubert identified on the news.

“The news published a picture of him, so it must be true,” Greenberg said.

“Yes,” Mikayla replied. “And I remember how he looked when he did that to us.”

Greenberg shot back.

“She said if it’s on TV it must be true,” he said. “So she adopted her version of who did it from the media reporting. It’s crazy.”

Great grandmother Regenia Trevathan disputes Greenberg’s claims.

“We’ve all been there as a child, an 11-year-old who forgets things, who lies on their little cousin. But you never, she will never ever forget that face that she pointed out,” she said.

While on the stand, Mikayla clutched PJ’s Pokemon card in her hand. Her great grandmother said she wanted a piece of PJ with her as she testified.