DNA tests confirm that Ariel Castro is the father of the 6-year-old girl held captive with three other women in Cleveland.
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Forensic scientists took a sample of Castro's DNA yesterday following his initial court appearance and worked thorugh the night on the case, according to the attorney general's office.
Castro, 52, is charged with kidnapping and raping Michelle Knight, Amanda Berry and Gina DeJesus over a 10-year period in his Cleveland home.
The 6-year-old girl, Berry's daughter, was rescued with the women on Monday.
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The news comes as sorrid details begin to emerge about the women's ordeal, including reports that Knight became pregnant five times during the 10 years and was starved and beaten until she miscarried each time.
Knight was also forced to deliver Berry's daughter in a plastic pool upstairs. Castro told her he would kill her if the baby died, according to a police report.
Unlike Berry and DeJesus, who are now home, Knight had to be hospitalized after her rescue for facial reconstruction surgery to repair damage done by Castro's beatings, her grandmother told WOIO.
She's also lost hearing in one ear.
According to local media reports, Knight was released from the hospital today "in good spirits."