LOS ANGELES (KABC) -- The biological father of the 8-year-old Palmdale boy who was beaten to death took the stand on Tuesday.
It was the second day of the penalty phase for Isauro Aguirre, the man convicted of torturing and murdering Gabriel Fernandez, his girlfriend's son.
The prosecutor showed photos of Gabriel's biological father, Arnold Contreras, and his son to jurors. Contreras said his family will never be the same after Gabriel's death. He explained that he was always against Gabriel moving in with the defendants.
He described how Gabriel was very energetic and kind.
"Was he loving?" the prosecutor asked, to which Contreras replied, "Very much so."
"He was always smiling," Contreras testified, and added that his son was "a normal kid" who liked playing games like "cops and robbers."
Contreras testified that Gabriel's mother, Pearl Fernandez, never showed any love toward Gabriel.
When Gabriel was tortured and murdered, Contreras said he was in prison for robbery and possession. Prior to that, he said he had been in and out of county jail.
Contreras described the day he learned about Gabriel's injury and imminent death.
"I was in Riverside County jail and the chaplain pulled me out, said he was on life support, and that they were going to take him off the next day," Contreras recalled.
"I felt... I don't know how to explain it," he said. "I felt hopeless, guilty. I should've been there."
The prosecutor asked Contreras, "If you were out of custody, would you have visited Gabriel like you did before?"
"Yes," Contreras said.
When asked what he would tell Gabriel today, Contreras said, "I'm sorry. I'm sorry for not being there."
Gabriel's father said he asked to see Gabriel in the hospital but "they didn't let me." He said he's forever impacted by Gabriel's death and can't sleep at night.
Jurors must decide whether Aguirre should receive the death penalty. This part of the trial is expected to last for 10 days.
The defense presented Aguirre's 10th grade teacher, who said the defendant appeared to need special education classes, but the bureaucracy of referring students was frustrating.
Whatever the backstory was for Aguirre, the injuries inflicted on Gabriel emerged in detail from those who treated him.
"I remember seeing a child that looked dead. He looked mutilated. He looked like a prisoner of war. I mean, from head to toe he was bruised and damaged," testified Emily Rebar, a registered nurse at Children's Hospital.
The jurors reviewed the pictures of Gabriel at the time of his death - all too awful to show on television. As they consider whether Aguirre should be condemned to death, they heard descriptions of what Aguirre did to the young boy.
"Bruising on his pubic area, the base of his penis," described child welfare worker Gabriela Robles, as she held back tears. "He had marks that appeared to be consistent with cigarette burns."
The doctor who conducted the autopsy said that charting injuries typically takes a day. For Gabriel, with so much trauma on top of malnutrition, it took two days. He described how tedious it was extracting nine BBs from his body.
"To make sure I got all the BBs, I had to take the body back into the X-ray room on the second day, fluoroscope the whole body to make sure there weren't any more metallic particles in the body," explained James Ribe, a forensic pathologist.
The boy's mother is awaiting her own trial.
Slain Palmdale boy's father: 'I should have been there'