I promised you all here that if I heard anything, I would post it here. This case is one of those that will affect and live with me for a long time.

The results on the father as to what he might have been on are in.

Definitely some kind of psychotic lunatic nut case, IMO. I am glad that he is not living anymore and further draining our system in the courts.

Feel free to read some of the comments attached to the clips, some of then really set me off.

Dad who killed toddler wasn't on drugs, report says

A stuffed toy dog was hung on the stop sign at the intersection of Bradbury and Blaker Roads west of Turlock a couple of hundred feet west of the spot where Sergio Aguiar, 27, of Turlock, savagely beat his 2-year-old son, Sergio Axel Casian, to death before being himself shot dead by a peace officer. Ted Benson/The Modesto Bee

Modesto Bee

Toxicology tests negative; behavior still unexplained
last updated: July 03, 2008 11:32:30 PM
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Toxicology tests came back negative Thursday for the Turlock man who beat his young son to death last month, adding to the mystery of why a father would commit such a heinous act.

Sergio Casian Aguiar, 27, had no drugs or alcohol in his system that might help explain his behavior, said Kristi Ah You, Stanislaus County chief coroner.

Aguiar killed his 25-month-old son, Axel, on June 14, the night before Father's Day, on a dark country road 15 miles south of Modesto.

Confronted by a passer-by, Aguiar only stopped kicking the child when a Modesto police officer shot him in the forehead, killing him where he stood.

The boy was pronounced dead at Emanuel Medical Center in Turlock. It took DNA testing to positively identify him.

The crime's brutality shocked the community and generated reaction from around the world.

Investigators and co-workers said Aguiar had no criminal history or signs of mental illness, though witnesses on the night of the attack said Aguiar spoke of "demons" within his son.

Aguiar worked in the meat department at a FoodMaxx store in Turlock and had separated recently from his wife, Frances Lilian Casian, a kindergarten teacher in Delhi. Casian was in Southern California for the weekend when the attack unfolded on West Bradbury Road, authorities said.

Nothing, Casian told detectives, foretold the tragic events.

Phil Trompetter is a psychologist who spent 30 years working with law enforcement agencies in Stanislaus County, providing police and forensic psychology. He sold the police psychology portion of his downtown Modesto practice, but kept the forensic psychology element, continuing to evaluate defendants and suspects while serving as an expert witness in the courts.

Trompetter spoke Thursday about the case, but emphasized his hypothesis on Aguiar's actions was based on media reports.

"I don't want to sound like I'm diagnosing this guy," he said. "But it sounds like brief psychotic disorder ... a delusional belief that his son was possessed by demons."

Trompetter listed four conditions that could have led a father to act so violently toward his son:

Substance-induced psychosis produced by narcotics such as methamphetamine, cocaine and PCP. This cause was ruled out by toxicology tests.

Chronic mental illness. Aguiar's family, co-workers and investigators said there were no signs of mental illness.

Delirium caused by a medical condition such as a seizure or long-term illness.

Brief psychotic disorder.

Trompetter said the final diagnosis is not common, but it could explain an acute psychotic break happening without previous symptoms "out of the clear blue."

According to the Web site WebMD, brief psychotic disorder is a short-term illness with psychotic symptoms that often come on suddenly and last for less than one month, after which the person usually recovers completely.

"They got crazy and then they cleared up quickly," Trompetter said of people whom he's diagnosed with the disorder.

According to WebMD, some people might have recurrent episodes of psychotic symptoms, but it is rare.

The symptoms might include hallucinations; delusions; disorganized thinking; speech or language that doesn't make sense; unusual behavior; problems with memory; disorientation or confusion; changes in eating or sleeping habits; changes in energy level or weight; and the inability to make decisions.

According to WebMD, there are three basic forms:

Brief psychotic disorder with obvious stressor occurs shortly after and often in response to a trauma or major stress, such as the death of a loved one, an accident, an assault or a natural disaster.

Brief psychotic disorder without obvious stressor has no apparent trauma or stress that triggers the illness.

Brief psychotic disorder with postpartum onset occurs in women, usually within four weeks of having a baby.

The disorder generally occurs first in early adulthood, 20s and 30s, and is more common in women than in men, according to WebMD.

Trompetter, however, could not recall a case of the disorder resulting in someone committing "such a heinous act of violence."

Bee staff writer Emilie Raguso contributed to this report.
Bee staff writer Rosalio Ahumada can be reached at or 578-2394.