The "Hot in Herre" rapper was performing during RoverFest in the city's Voinovich Park on Saturday when he introduced Berry and a friend during his set, according to the Cleveland Plain Dealer.
Berry, 27, who was 16 when she disappeared in April 2003, had been held captive with two other women -- Gina DeJesus and Michelle Knight -- for 10 years. The women lived under brutal conditions in Castro's home in Cleveland, and Castro fathered a child with Berry during her time there.
Castro, 52, accepted a plea bargain Friday with a recommended sentence of life in prison without parole plus 1,000 years. Castro had been indicted on 977 counts, which spanned the period of the women's captivity and included charges of rape and kidnapping plus two counts of aggravated murder for accusations that he starved and punched one of the women while she was pregnant until she miscarried.
The number of years in the recommended sentence -- the sentencing hearing is scheduled for Thursday -- would ensure that Castro dies behind bars and void the possibility of Berry and the other women participating in a grueling trial. The death penalty was waived as part of the deal.
The women had been fairly quiet since they were released from Castro's home, save for the first spoken statements they made in a video released earlier this month.
As Nation Now points out, the Saturday appearance was somewhat notable because Nelly's star was burning brightest just before Berry disappeared in 2003.
Nelly, 38, real name Cornell Iral Haynes Jr., told MTV News that the moment wasn't planned and added that Berry served as an inspiration to him.
"I had a chance to meet and greet fans before the show and she was there with her family and friends," Nelly said. "After we took pictures we had a chance to sit down and talk, and I told her that she and her family were more than welcome to come up on the side of the stage and they did."
"When we got to 'Just a Dream,' I wanted to make sure that we had a chance to acknowledge her," he said. The rapper dedicated the song to her during the concert.
However, he did not expect the moment to attract that much media attention. He told MTV that his intentions were to show Berry love and support.
"I just wanted Cleveland to know that we were proud of her and that the strength and the pulse of the city is built around the people," he said. "To see her survive that, I thought it was amazing and it inspired me to do almost anything."
Nelly introduced her to the crowd and she smiled and greeted the crowd with a wave.
"He said, 'Everyone, here's Amanda Berry,' and she came out with a friend, another young woman," concert-goer Kayleigh Fladung told the Plain Dealer.
"She didn't say anything, but she was smiling and happy. She waved to the crowd, everyone went crazy cheering, and she went backstage. Nelly did his set, four or five songs, and then he brought her out again and everyone cheered."
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