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This May 24, 2010, file photo provided by the Wake County (N.C.) Bureau of Identification shows Ann Pettway, who snatched a newborn baby from a New York hospital more than two decades ago.

Updated 4:35 p.m. ET: A woman who snatched a newborn baby from a New York City hospital more than two decades ago and raised her as her own was sentenced in a Manhattan federal courtroom to 12 years in prison Monday.

Ann Pettway, 51, received less than the life sentence she was facing and the 23 years the mother of the kidnapped girl requested.

White’s father, Carl Tyson, expressed his disappointment, saying, “I’m not really satisfied with the sentencing.” He added that Pettway “put a scar on me.”

Pettway pleaded guilty to a kidnapping charge in February.

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During her court appearance then, she offered few details of the 1987 kidnapping. She said she took a train from her Connecticut home to Harlem Hospital, where she scooped up 3-week-old Carlina White, who had been brought to the emergency room by her parents.

"I went to the hospital. I took a child. It was wrong," she told the court.

But she offered no explanation for her action.

As part of Pettway's plea bargain, prosecutors recommended that she be sentenced to between 10 and 12½ years in prison. 

Carlina's birth mother, Joy White, wept during the February proceedings. "I've lost 23 years of being with my daughter," she said, adding that those decades were filled with pain and heartache.

White said she encountered Pettway at the hospital on the day her daughter disappeared, dressed like a nurse. "She came up to me and said to me, 'Don't cry. Your daughter is going to be OK.'"

The case was solved by Carlina herself.

Woman pleads guilty in 1987 newborn kidnapping case

As she grew up in Connecticut under another name, the girl became increasingly suspicious of her own identity. Pettway told her she had been given away by a drug addict.

Carlina White said she browsed the website of the National Center for Missing and Exploited Children for clues to her identity. After matching a photo of herself with one on the site, she tracked down her true mother and they reunited in January of 2011. A DNA test confirmed they were mother and child.

Today, they speak every day, Joy White said.

"I love my daughter. She's a beautiful girl," she said, adding that she had kept a picture of her missing baby at her bedside for 23 years.      

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