Olathe ? A Lenexa woman was sentenced to 20 years in prison Thursday for the death of her fiance’s son, a stiffer sentence than her attorneys had expected under a plea agreement.

Jessica Dawn Harber, 25, had pleaded no contest to a reduced charge of second-degree murder in the March 2005 death of 18-month-old Dakota Smith.

Harber was engaged to Dakota’s father when Dakota suffered head injuries in March 2005 and died.

She told authorities that Dakota fell and hit his head on a table in her apartment when she was in another room. But medical experts testified that there was no way the injuries could have been caused by an accidental fall.

During a hearing Thursday, prosecutors asked District Judge James Franklin Davis to increase the sentence after Harber’s attorneys insisted she was innocent and asked for a jury trial.

Davis agreed with prosecutors, saying he had no doubt Harber was criminally responsible for the boy’s death.

Her attorneys, who had expected a maximum sentence of 12 years and three months under the plea deal, said they would appeal the stiffer sentence.