A Dale City teenager who admitted that she killed her 11-month-old daughter by shaking her and hitting her head against a support beam was sentenced yesterday to 15 years in prison.

Angelina Marie Yannello, 19, sobbed in Prince William County Circuit Court as she apologized to her family and to her late daughter, Caitlyn, saying that she never meant to hurt the baby. Judge Frank A. Hoss Jr. sentenced Yannello to 30 years in prison for felony homicide and felony child abuse, suspending 15 of those years.

"Mommy loves you very much, and I miss you and always will," Yannello said through tears, directing her comments to her daughter. "I was not ready to be a mother, and there is no excuse for what I did to you.

"The greatest punishment is having the rest of my life knowing that I am the one who killed my daughter."

Caitlyn died last September from what doctors described as a serious skull fracture and other injuries consistent with shaken baby syndrome. Yannello had told police several stories about how the injuries had occurred, including that her daughter was hurt when she fell backward while sitting on the floor and that she had thrown a tantrum and had hit her head on a coffee table.

When entering her pleas in May, Yannello took responsibility for killing Caitlyn, saying that she shook the baby and then accidentally struck her head against a support beam in the basement of a Prince William home.

Assistant Commonwealth's Attorney Sandra Sylvester described the act yesterday as "a brutal assault on a helpless, innocent baby" and said that doctors and police investigators described her injuries as being consistent with "being swung like a baseball bat."

Hoss did not comment on the case before handing down the sentence other than to say that he believed the sentence should go beyond the recently adjusted sentencing guidelines, which called for just more than seven years in prison. Yannello pleaded guilty to the two charges as part of deal with prosecutors, who dropped an additional charge of murder.

Chris Alexander, 20, the Woodbridge man who was determined by paternity tests to be Caitlyn's father, attended the hearing yesterday with his mother and said he agreed with the sentencing.

"I think that she deserves what she gets, and I don't even know if she's remorseful," Alexander said softly. "I just hope no one else does this to their children."

Yannello's parents, Mike and Tina Yannello, said after the hearing that they believe their daughter should serve time in prison, and Mike Yannello said that he suggested to prosecutors that they recommend an 11-year sentence--one year for every month of Caitlyn's life.

"I don't care if it's my daughter," Mike Yannello said. "If she did it, she needs to be punished."