RIVERSIDE – A Riverside mother killed her developmentally disabled son by delivering a fatal head blow to stop his crying, a prosecutor alleged Thursday, but her attorney said the toddler's death stemmed from his condition that had been worsening for weeks.

“Matteo died from abusive head trauma,” Deputy District Attorney Ambrosio Rodriguez told jurors in his opening statement in the trial of Cecilia Angelita Ochoa.

“These were blows that she inflicted,” the prosecutor said, gesturing to Ochoa. “That woman right there killed her son.”

Ochoa, 31, is charged with first-degree murder and assault on a child resulting in great bodily injury in the Feb. 25, 2003, death of her 3-year-old son, Matteo.

The mother of five exhibited a “pattern of abuse and neglect” where Matteo was concerned from the day he was born, Rodriguez said.

Within months of his birth on Sept. 7, 1999, the tot was diagnosed with hydrocephalus, a brain disorder marked by enlargement of the head from subdermal swelling, Rodriguez said.

The disorder – sometimes known as “water/jug head” and affecting one in every 500 live births – causes spinal fluid to build up around the brain, leading to an impairment of cognitive function.

“He was mentally retarded,” the prosecutor said.

The child was fitted with a shunt connecting his head to his abdomen, concealed under the skin, draining the fluid around his brain.

After Ochoa gave birth to Matteo, who was 10 weeks premature, she was rarely seen visiting the baby on the neonatal ward at Loma Linda University Medical Center, Rodriguez said.

After leaving the hospital, Matteo “had no one to take care of him,” he said.

“The poor boy lived in filth,” the prosecutor said. “His playpen at home smelled like old rotten food. His clothes were dingy. ... His (older) brother and sister had open sores on their heads with lice crawling out.”

The child was enrolled in a special needs program, but was absent a majority of the time, Rodriguez said.

He said Ochoa told police three different stories about how Matteo died before finally breaking down and admitting she slammed the child's head into a doorway to make him stop crying.

According to the prosecutor, the boy was cooped up in his room, kicking the door, when Ochoa apparently lost her temper. After knocking her son to the floor, the defendant “held his head in place as he struggled to live,” Rodriguez alleged.

Post-mortem photographs of the boy's face, shown in court, revealed finger marks on his right cheek.

Rodriguez said Ochoa let six hours elapse before contacting authorities about her son's death.

Police officers testified they found the boy's lifeless body on his bedroom floor, a pillow under his head and blanket laid over him.

Defense attorney Mark Johnson disputed the prosecution's contention that Matteo died from acute head trauma, saying the neurological experts that he consulted – who will be testifying – determined the child suffered a “chronic subdural hematoma.”

“The injury was weeks old,” Johnson said. “Something happened to cause this condition over a period of weeks.”

The attorney said Matteo's hydrocephalus caused increased pressure around his head, which sometimes led the tot to bang his head into objects, possibly for relief.

“He was a very sick little boy,” Johnson said. “The child had a condition that killed him. It's not Cecilia's fault.”

According to the defense attorney, his client tended to choose boyfriends who physically abused her and fathered her children without wanting to make any commitment to help raise them.

Ochoa, who has no known prior criminal history, had three children before Matteo and two children after. One child died at four months from spinal meningitis. The other children are in foster care or living with family, according to the prosecution.

The man with whom Ochoa was living at the time of Matteo's death, 27-year-old Leon Carr, is facing felony assault charges for allegedly beating the defendant so badly last September that she required reconstructive surgery, according to Johnson.

The attorney said the reason Ochoa waited to call police after finding her son dead was to give Carr sufficient time to leave her Magnolia Avenue apartment because Carr did not want to be interviewed by authorities.

Investigators initially believed Carr had something to do with the tot's death, but dismissed him as a suspect after Ochoa said he was not responsible, according to Johnson.

He said that in addition to hydrocephalus, Matteo suffered from respiratory distress syndrome, anemia and acid reflux.

“Handling a child like this would be beyond most of our capabilities,” Johnson said.

He described Ochoa as “a good mother” who loved her son.

According to Johnson, Ochoa accidentally hit her son's head opening the door to his room, but that wasn't enough to precipitate his death.

“The bottom line is, what killed this child did not happen within two weeks of his death,” the attorney said.

If convicted, Ochoa could face 40 years to life in prison. She is free on $100,000 bail.

The trial is expected to last three weeks.