(CNN) Two decades after taking a baby from a hospital and raising the child as her own, a South Carolina woman pleaded guilty Monday to kidnapping and interference with custody, prosecutors said.

Gloria Williams, 52, allegedly posed as a hospital nurse and took Kamiyah Mobley only hours after she was born on July 10, 1998, at a Jacksonville, Florida, hospital. The infant's mother, Shanara Mobley, told investigators a woman she thought was a nurse entered her room. The new mother asked the woman to place her daughter in a baby carrier, but the nurse instead left with the newborn, according to an incident report filed with the sheriff's office.

Authorities said Williams used fraudulent documents to establish a new identity for the child and raise her in Walterboro, South Carolina, northwest of Charleston. That child, now 19, goes by the name Williams gave her -- Alexis Manigo.

Prosecutors are seeking up to 22 years in prison on the kidnapping charge and up to five years on the interference charge under the negotiated plea deal, said David Chapman, a spokesman for the Florida state's attorney office for the fourth judicial circuit. Sentencing is set for the first week of May.

"This is a range that we are good with, zero to 22 years, but it will be up to the judge to decide," Chapman said

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