New York ( CNN ) -- A woman who stole an infant from a Manhattan hospital in 1987 pleaded guilty to a federal kidnapping charge Friday and could face at least 20 years behind bars . Ann Pettway has been charged in the abduction of Carlina Renae White , now in her early 20s , who was reunited with her biological mother last year . Pettway pleaded not guilty to the kidnapping charge last year . Who would steal a baby , and why ? Carlina White was 19 days old when her mother took her to the Harlem hospital with a fever more than two decades ago . The mother , Joy White , testified that she went home to rest and returned to the hospital to find her baby missing . `` Ann Pettway preyed on me , '' Joy White said Friday , adding that she remembered seeing Pettway at the hospital . `` All I want is justice , '' White said . `` This is too much for me and my family . '' The grand jury said Pettway had `` willfully and knowingly '' seized the baby . She turned herself in last month at the FBI office in Bridgeport , Connecticut . Report : Pettway frustrated with miscarriages . `` I raised her as my own and I knew it was wrong , '' Pettway said Friday . The younger White , who was raised under a different name , long had a nagging feeling that she was brought up by a family she did not belong to , Ernie Allen of the National Center for Missing and Exploited Children has said . CNN 's Laura Batchelor contributed to this report .
NEW : Ann White will face 20 years behind bars . She was arrested on a federal kidnapping charge . Young Renae White , now in her early 20s , was taken from a New York orphanage in 2007 . White was reunited with her biological mother last year .